Thanks for the answers about the SRK vs. M6 potential brightness.
It looks like the SRK is definitely all over the board for current draw. Here the reviewer got 7.5A whereas in this thread they measured between 6.63A and 5.35A. So I guess it’s hard to predict how bright this new M6 will be in comparison. Like markito said a few posts above, I also wouldn’t mod this if I bought it, so out the box brightness is all I would get.
It appears that the SRK can be used with less than 4 batteries if desired (because they are in a parallel circuit). So the same goes for the M6, correct?
Another question: How much parasitic drain would the M6 pull on the switch when turned off, and is lockout possible?