I had the same dilemma a few months ago. After a lot of reading I chose the MMM 2200KV, and damn it's fast. I am traditionally a Novak user, but this time I went with the MMM. Alot of other guys were saying with the E-Revo the Novak HV system had a tenancy to over heat, so that made me lean towards the MMM. I am running two 7.4V 2S 6000mAh lipo in series (so it's like having one 4S 14.8V 6000mAh battery) and it's fast! Also there seems to almost no heat build up on any components, so I am sure I can get more speed out of the system, and I get about 15min of run time. I just ordered two 3S batteries, so that should take it up a notch. As some one else stated their customer service is great! Programming is also a breeze with the PC link, much much better then the Novak (I have a few other Novak brushless systems). So I think the MMM is the best for the E-Revo, it's worth the extra bucks!
Once you have tasted flight, you will forever walk the earth with your eyes turned skyward, for there you have been, and there you will always long to return - Leonardo da Vinci