Oops - didn't see these replies til now.
guardior - well if I would do the mod, I would definitely do DD in a UltraFire/Convoy C8. I used to be much more conservative in worrying about high amps, but now, I flipped nearly completely around. I find it hard to go back to 7135 based drivers now.
Here's my reasons:
- it's nearly impossible to burn out a CREE LED in a DD configuration when it's mounted on a copper DTP MCPCB (assuming avg/good heat junctions to the body) - you really don't have to worry about that at all - this I didn't know 1-2 years ago. The forward voltage (Vf) level of the CREE LED's will always keep the amps to moderate levels, plus as a cell drains, the amps will naturally drop because the voltage level continuously drops, again, it's a natural protection mechanism all based on the forward voltage (Vf) of the LED .
- you can set up any light for max output, then if you don't want that, use a standard cell like a Pana B to run at lower amps, or comprising will a 10A rated cell like a Pana PF or Pana BD, etc.
- implement a turbo timeout to keep the heat from getting excessive
- a light left on high/turbo til it gets too hot to even touch still causes no damage. Well I dunno if this is always the case, but it happened to me twice: once with a modded out SupFire M6, once with a 18650 EDC configured at 2.8A, and both times there was no perceived damage to any parts, including the cells.
Hope this helps. Again, it's all personal opinion/usgae, or subject to the target user. Certainly if I were to give/sell a modded high amps or DD light to someone not knowledgeable of the risks and has small kids that will have access to the light, I would be VERY concerned about putting that light in their hands that didn't have temperature monitoring based amp control.
Ronin42 - as RMM mentioned, amp max capabilities of the cell are not obtainable for a DD set up of one cell with one CREE XM-L2. The Vf requirement of the LED will limit the max amps. There's some really good data posted here on BLF showing the Vf levels compared to amps (for example, see post #51 here: https://budgetlightforum.com/t/-/19546). The higher the amps, the higher the Vf is, so typical 3.7 Li-Ion cells can't deliver a high enough voltage level to drive a XM-L2 at 10A, or even 8A. Highest I've been able to achieve is ~6.5A.