[lincpimp]

5s will run cooler, and will draw approx 1/5 less of the amps of the 4s setup if both are geared for the same top speed. In my experience 5s is a noticeable gain in power and runtime, with not much extra weight. As far as running 70% expo, just regear for the same top speed, escs run cooler at full throttle than partial.