WWSTWD?

In a situation as you describe, I’d jump before I was pushed.

Staying

Do you think the the sunk cost of staying where you are now will bear fruit in the long run? Do you honestly think that you're going to be given your marching orders or is that your head telling you that's going to happen. If you pre-empt that conversation (sales aren't where they need to be, here are the reasons, where do we go from here) with senior staff will that make your situation better in the next 2-3 years. Will they match your offer? what will happen if you tell them?

Moving.

What do you know about the new company? Will not having specialist knowledge put you at a massive disadvantage with your peers. What's the time scale to move to senior management? What is that position? Does it exist? Is it just a lure?

If you know your old boss is good at his job and you work well with him, go for that. You can learn the new subject matter, but you obviously have the core necessary skills, or he  wouldn't have asked you.

Regardless of a new strategy, your direct manager is not supporting you like they should, and that may continue through future blips.

Yeah, if the old boss wasn't part of the "serious problems" then I'd be tempted. If your current management recognised you're a good salesperson that's just been landed with a crap product presumably they'd already be letting you know not to panic

I'd be asking your old boss for a salary that matched my income expectations without needing commission. If he has faith in his product/company/experience then he should be able to match that and you're then relieved of a major pressure / stress in your life. If he's not willing to do that then that shows lack of confidence on his part and then it does seem like a frying pan to fire jump.

Old boss stuff
Is the new stuff that your old boss is selling any good?
Do you like and/or get along with your old boss?
Do you have faith in your old boss being successful?

Current situation stuff
How will a new structure in the current business help you sell more of the product?
Are there going to be changes to the product/market/customer base that will help improve sales?

TLDR
What @Jam-bo said

Edit: How much flying is involved with each role?

Only you can make the call, some good points raised above.

If I’m not wrong you are late 40s/early 50s? In which case “mentoring up to management” sounds like the kind of carrot you offer somebody in their 20s. By this stage of your career you should be looking to get what you want, and not put up with vague promises of what might happen in the future

I'd be looking further afield - both options sound a bit meh.

Have a word with some recruiters, let them know you are looking and see what other markets are available - good sales people can switch roles - just because you've always sold X doesn't mean you can't sell Y.

What was life like under the old boss?  If I recall correctly you’ve been in the frying pan a while. Recalling why you’re not still working for them at the moment/ what made the current role seem attractive might provide some useful perspective.

a) it turns out there were found to be various serious issues in the company

Is b in any way responsible for a? If they were then you may be going from one frying pan to another.

Is there any way to seek reassurance that the structural issues causing the sales problem are and will be taken into account with regards to your performance monitoring (although clearly timescale for this may preclude it happening before old/new boss wants an answer)?

I'll try and answer those questions in the adopted style:

Staying

There are signs albeit full detail isn't revealed that peopler aware of and changing the software direction to accommodate success, elsewhere in the world there's a big potential market for it, UK needs a unique selling point.   As per NickC, its my head telling me this, my package is very good but I'm only earning half of it because no commission.  It could well be the revised strategy / next 2-3 years are good, its a PE after all and they need to raise the company value.  But its a PE, and losing my salary on the basis of my sales performance is an obvious saving/scapegoat option in my head anyway.

Going

I worked well with old boss and we understand each other, and yes he wouldn't have asked me if he didnt believe in me because my performance reflects on him.  The path is to replace him as he moves upwards, a strategy he's agreed for himself with the CEO, so yes, its real.  I'd have start start as "new business" though, whereas I'm an "Account Manager:" sales persona.  The company is 20yrs old Tech org but in a recent period of re-investment current performing at over 120%, young high performers, global although needs 3 days in a London office whereas I work from home mostly now.

Is b in any way responsible for a?

No, he never worked at my current company.

If I’m not wrong you are late 40s/early 50s? In which case “mentoring up to management” sounds like the kind of carrot you offer somebody in their 20s.

Its Senior Management, VP Sales UK ( I hate the VP bit!)

You can see how its quiet hard to make a decision...

IIRC you've posted a few times about the struggles in your current job. From how I read it each time you're clearly not happy there. If it's the same/similar money and a chance of being a lot happier I'd take it. You don't owe you currently employer anything if they're treating you shitly.

 I’d have start start as “new business” though, whereas I’m an “Account Manager:” sales persona.

That's a big change in role. Could you make that change into a market that you don't know?

But its a PE, and losing my salary on the basis of my sales performance is an obvious saving/scapegoat option in my head anyway.

You know that's not how it works though.

Move, sounds like a no brainer to me, you know the boss, they know you, that's a great starting point. You'd be walking away from a nightmare which has been clearly hitting your mental health. It's a new role but you won't progress unless you take opportunities when the ariase and ones like this don't come up that often.

If your job is to sell widget A and getting 50% of your take home is based on selling widget A in bulk but that same widget is, by the sounds of things, a Lemmon no one wants to buy, then I'd be moving myself.

No real harm in moving to work with your old boss for a while whilst keeping an ear out for another opportunity if it doesn't work out.

BUT, having read a couple of threads from you on a similar vein, frankly working in Sales sounds pretty awful. Have you thought about moving  away from sales?

Take up the offer

In 6-12 months time if you're not posting on here about another work related existential crisis it was a success

Have you thought about moving  away from sales?

I have flirted with the idea.  I'm former professional services although that games has moved on a bit since I left, and therefore although the idea of returning as a Director to manage a team appeals, I'm not sure how successful I'd be.  But with a mortgage soon ending even lower pay for a happier balance appeals to me.

What other roles are typical for ex Sales people?

In 6-12 months time if you’re not posting on here about another work related existential crisis it was a success

PMSL, thanks ElShalimo, sadly you are correct... 😀

If the status quo option is getting you down, and there's a more exciting option to move onto and try...

I've been out of enterprise IT sales for quite a while now so can't offer any current advice but I was mostly in new business.

I think that transitioning from account management to new business can bring a better skill-set to the role. Certainly better than going the other way, as I found out.

Good luck whatever you're decision

Does it pay more?

Don't over think it

"Subject to negotiation"
+
"Need an answer now"
=
Spidey senses tingling

Negotiate THEN answer

IIRC you’ve posted a few times about the struggles in your current job. From how I read it each time you’re clearly not happy there.

This

I’m constantly being rapped over the knuckles for poor sales by my direct management, although our revised senior management team are aware and addressing all the issues.  As a long time sales person not meeting quota my expectational paranoia is of  having a painful conversation at the end of the year, possibly having to find a new job

Are they building up to sacking or redundancy?  if the former is it reasonable and will you have grounds for unfair dismissal, if the latter what would the package look like?

is there a third option of negotiating a voluntary redundancy now so you can take new post with a bit of a financial life raft  = best of both worlds

They both suck.

You're struggling to sell a poor product now.  You can hop to a new market , which you don't know about, and try to sell a potentially poor product there.  That doesn't sound too clever to me...

I abhor sales people who don't have sufficient technical knowledge, and I see them a bit too often. Don't become one of them

I abhor sales people who don’t have sufficient technical knowledge, and I see them a bit too often.

Disagree. Good people (with good support around them) will learn quickly, or find good solutions /answers if they don’t know themselves. If we followed your thinking people would never change direction and try new and potentially better things. Growth mindset and all that.

Haven't read through all of the responses, but I'd be thinking about what is going to motivate me more and who will I enjoy working with more.

We spend so much time at work, it's crazy not to be working with people you like, doing something you enjoy.

Unless I was certain the problems with your current product are likely to disappear entirely, I would be looking for a good 'out' strategy.

I went from RSM to business dev a few years ago. The increase in money seemed like a great idea, but I hated the process—lots of grinding for leads. In the end, I moved into a training role for a product line that I knew very little about. It was certainly stressful for a while learning everything, but I'm happier doing it. I still work with customers, I'm involved in the development of new products, and I basically have the things I liked about sales but with no targets. Pays a bit less, but monthly requirements are less now. Personally, I don't know if I'd feel great learning a new product while also hunting. YMMV. Is there a 3rd option you could find?

"They both suck."

Is a much shorter way of saying what I just rambled through!

Youve posted about this before and unhappiness.

Youre not going to met the sales expectations for year end.

Your already getting grief for it right now.

Your going to get unceremoniously binned year end, if not before.

Leave on your own terms and do it now.

Now for the quotes: All jobs are 5hit, only the depth differs/your only as good as your last fk up.......

3 days in a London office? You'll be needing a new watch.

Your going to get unceremoniously binned year end, if not before.

Just been informed that I'm demoted aka offered a role 1 step down the ladder because "its a better fit for me" as part of a re-org, publicly in a meeting and currently without consultation.

Leave on your own terms and do it now.

Plan B...

“Hi, is that the constructive dismissal lawyer? Yes I need to sue someone.”

Well, at least they've told you what they want you to do I guess, so it at least removes the doubt. 

Just been informed that I’m demoted aka offered a role 1 step down the ladder because “its a better fit for me” as part of a re-org, publicly in a meeting and currently without consultation.

Oof!

Look on the bright side, at least they're really really stupid....

Until the formalities occur, the implication is same OTE, less responsibility and I have some skills they need / want me to help mentor in others. I'n not assuming my time there is any longer than my notice period - triggered by either party - from here on in.