sorry bro but which motor and pinion and why you guys still think the cyclone S is still so much better than the sprint 2? and the cyclone S is full plastic compared to the sprint 2

just because it is easier to chnage belt and ball diff? why does the ball diff help?

do I have to buy a spur gear as well?

and if i buy separate like this , is it even better than the cyclone s rtr kit?

thanks for your help