So many questions

[neweuser]

I run the quark on 5s lipo....no probs with it. But the esc is up to you. If you get the quark, get a neu, they are way efficient and help run the controller cooler too. Otherwise, cost wise, you could get a 12020/9xl feigo, ultimate ubec, and if you go lipo, get a lvc.

The tranny should be fine, not sure about the slipper, i would get a strobe if you can find one.....gearing depends on what you run as a motor and batteries, weight, diffs etc....