Rustler VXL Setup

Hi guys,

Been reading RCM for some time now and i took the virus :)

So i bought myself a rustler vxl roller. I've always wanted a RWD.
The build is pretty much on a tight budget, for now, so i've settled on Kershaw's 80A combo (the EzRun and Revolver S).
I have a 76T spur, and was thinking of Robinson's 72T steel one.

What would be a good top speed to gear for using that setup? And should I go 3S, or settle for 2S?

I should mention that i have 2 race-tracks around here where i'm gonna learn to drive it, onroad and a loose-dirt offroad track.

Thanks