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Just recieved one of these 3x XML bad boys from China. Turned it on and it's a nice floody beam. Low-Mid-High-Flash-Off modes. There's lots of them on ebay for around £35 delivered. [img] 
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(picture is from another vendor)
But wait a minute comparing it to my single XML it's the same brightness. I start wondering if I've been sold a 3 XPG but the led's look similar to the single XML light. Pointing it at a dark surface close up reveal its got one bright led and 2 very dim. So I take it apart and find its got a 2 channel driver circuit both channels giving out 2.8v . One led driven from one channel and the other 2 LEDs are wired in series to the second channel. I've re-wired it and soldered 1 LED per channel (one led is now disconnected) and now it's brighter than the single XML light but it's 2 LEDs driven not 3.
I suppose it's still value for money and bright enough with 2x XML but I would much rather run 3 at lower power where they're more efficient than 2 at full throttle.
There's a bit more on these lights on the massive Bikeradar lights thread... I've got one on the way to have a play with, see if I can get it working right.
Ah [url= http://www.bikeradar.com/forums/viewtopic.php?f=20005&t=12807034&start=1180#p17939012 ]this[/url]. 67 pages took some finding.