What batteries to buy and why?

I got my Kokam 4800s in today. Having only had experience with "budget" packs, I was surprised to find that the Kokams have pcbs at both ends of the pack. Although I'm sure that they serve a purpose, I am now concerned that these might break.

Other than the concern about the pcbs, I do have to say that I am thoroughly impressed. These things put out some current. Of course, I don't have any measuring equipment, but I can make an observation. My truggy is running with a lot more zip with every snap of the throttle. I can't wait to get these out on the track to see how they perform. More specifically, I want to see how hot they get, as I tend to run my packs from fully charged until the lvc cuts out.