From my experience with MA, they work great for the money. However, they really should not be rated at 20C. IMO, they are solid 15C packs, but any more than that and they start heating up. The same thing happens with anything if pushed at or over its rating.
If you have the room and don't mind the extra weight, go with a higher capacity pack so that each cell doesn't need to have such a high C rating. You get the current and the runtime that way. For racers, this isn't viable since weight can be a deal-breaker, but bashers don't usually care.
Discharging to 0v and/or shorting cells is not good for any brand pack. (Shame on you GD
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