I try to avoid KD whenever possible since they refuse to communicate with me (I've yet to receive a single non-automated response), so I am afraid I can't answer your first question. Sorry. But both programmable K-106s I have work just fine on either 14500 or regular AA. They are much brighter on 14500 but work without a problem on either NiMH or primaries. I use 14500s at least 90% of the time and these two used to be my EDC lights for quite a while last year; I just went back though to check and both still work on NiMHs.
Somebody got one here just a couple of weeks ago, posted at the end of this thread:
Works fine on AA, but will be brighter on 14500. Still not the brightest light, but I don't think there are any programmable lights anywhere in that price range.
No way. Even on a lithium-ion it isn't. Maybe 180 lumens tops. On a AA battery it's more like 100-120 lumens. Those estimates may be a little generous. I put a XP-G in mine and it still isn't all that bright.
My Akoray K106 was pretty bright on a 14500, but after i let someone else use it, it is not that bright any more. The led seems to be darker (brown) so i think it has been much too hot.
On a nimh, it is about 20 lumen, and maybe 80 lumen on a 14500...
Maybe i should replace the led.
The Ultrafire C3 SS Q5 is much brighter, even the original C3 (P4) is brighter than the Akoray K106.
Sounds like the LED is partially burned. Since the 106 doesn't drive the LED that hard in the first place (at least not the 3-mode programmable) then it may that it came unstuck from the pill or they left out the thermal glue in the first place.
It's not too hard to replace the LED. I just replaced mine for the second time. The first time I put a cool white XP-G R5 in when those first came out and I just recently put a KD neutral R4 in there. The only problem is there is a hole in the pill that the LED covers, so the board the LED is mounted to should be 14mm (10mm probably wouldn't work and wouldn't transfer heat very well if it did). I think I must have done it right because the flashlight seems to get hotter now than it did before.
Ok, i was unlucky.. 2 recent order received the right flashlight. Mine was wrong... Hope they send answer me and tey decide to send me the right flashlight...