[suicideneil]

My comment: Has nothing to do with A123 cells, at all. I've been running them from day 1 and the MMM V1 works perfectly. I've used them with the hvmaxx 6.5 motor, and the 2 different 9XL clones, and the esc didnt bat an eyelid.

The key thing to bear in mind is that cheaper or lower spec (MA) lipos will drop their voltage just as much under load, and nimhs will drop their voltage even more so. My feeling is the issues are down purely to parts in the esc, bad layout or design of the esc, or just plain user related issues- poorly mounted esc being knocked about & using busted servos that overload the BEC spring to mind...