motor selection... E-Revo

[Patrick]

You can't just look at mah for your runtime, you have to look at watt hours.
Watts = amps x voltage
So a 4s 8000 milli amp hour (8 amp hours) battery will be 14.8v x 8 amp hours = 118.4 watt hours.
A 2s 16 000 mah battery will be 7.4v x 16A = 118.4 watt hours.
No matter which way you wire those cells up they still have the same total amount of energy, so the 4s 8000 mah setup will be better, because you need half the amps to make the same power (watts). Too many amps puts more stress on things and any resistance through wires etc. becomes more noticeable.

Personally I think for a neu 1515 30-40k rpm is enough for normal use.