I now have about 3 months with the 3S 5000 20-30C zippys racing several times a week with two different trucks E-revo and e-maxx using the MMM 2200 combos. I can say these batteries are as good as any other battery i have bought for this application - includes neu energy and maxamps. Yes I gear for 40-45Mph. I have run them however geared for 55mph going up and down the street until we were bored with no issues.
I will point out that when going down to 4S with the neu energies the batts get VERY warm which is ok given the different voltage and increase in current.

I think all of this talk about zippy not safe with a MMM is hogwash. I have 3 MMM and had failures long before i got into the zippy batts.As a matter of fact i havent had a failure since we have been using Zippy's. Are they as high quality - i am not going to even try to argue because i am sure in extreme situations they arent as good as Mike's batts because we are sure they arent.
However I had a buddy open up a zippy-H and compared serial numbers to the PQ - guess what they are similar - their is a belief that these zippy H's are PQ Enerland 30C rejects - thats why they put 20-30C on the batt. for 50 dollars i can buy 3 of these vs a neu energy equivalent. I can say that they seem to be holding up better than the older generation of Maxamps batts 6000 and 8000 i was using till they all puffed. Although we have had much better performance out of the 8400 35C Maxamps (no puffing).
Time will tell for sure - ie how long will these batts last - how many cycles.

In the end its nice to know mike has the best batts if you need them.