Which C8 XM-L would you choose if you had to do it again?

How about the KD C8? Here is the 5 mode with OP reflector. There were reports of under-driven models, but mine proved to be driven at 3A once I made my own thicker meter leads.

This is the only C8 XM-L I have, so I can't compare it to any others. I do like it and haven't had any issues.

-Garry