Not to try to take the opposite view, but for LED-based lights I found the L6 did not worked "well enough" for me so I sold it after a short while. I even (with help from CM) was able to mod mine to run at 1Amp, and although "reasonably" bright, I found the U2 a much better light to own, since both had similar beams. Since I like the U2's beam better, and since the U2 was smaller, and since the U2 worked perfectly with bare 18650 cells, I sold the L6. Basically to me the L6 had limited sidebeam, and OK-trow, so it really never did anything just perfect to justify keeping it. The U2 is simply a much better 5W light (to me).
I also was lucky enough to build my own 5W LED Lamp replacement module for the Turbo Head, and with an WX1T 5W with a Downboy 1000 I got a much more usefull light than the U2 or L6 ever could (which makes sense given the much larger Turbo Head reflector). Over the last few months I have sold the L6, then sold the U2 (since it wasn't geting much use at all), and recently my M4 (which used to be the host to the 5W LED module) so that I can purchase some new lights and the M6 that I just purchased from the on-going group buy - this M6 will become the new, longer running host for my 5W module
I am glad I was able to own an L6 and was able to play with it for a short while, but it is unlikely that I would ever own a KL6/L6 again. If I wanted a relatively small and great 5W light from SF I would rather buy the U2 - which you can now buy from the GB for about $205 bucks!
Will