I don't race, I bash at an relatively unused, but groomed, church softball field. Only in the grass in late fall and early spring, otherwise I run on the dirt/dust/mud depending on rainfall.
I've been running 2-4200 NIMH traxxas packs. I usually get about 30 total minutes of run time. ESC and motor temps always good with my gearing and driving. This in a slash raptor velineon.
So.....would you recommend buying two packs to give me about the same runtime or one larger mah pack for that runtime?