4S Trakpower or Maxamps for 8XL/MM Combo?

I have to say, while I've been using LiPo for two seasons, there are lots I don't understand. I'm very surprised so many of you are saying the Trackpower packs over the MaxAmps...why? Is there some technical reason I'm not seeing? Oddly I've been using FMA 3200MAh Scorpions running in a 4s Config and while they are small, they always fed my brushless monster just fine - although after about 6mins they were spent. LVC would trip. This year I'm looking at getting some new packs as well and I had been eyeballing those new 5K packs from Maxamps....is that a mistake? Why?

DM