RE: 1/10 or 1/8 faster?
I think the thing with 1/8th's is they are made for proper groomed racing tracks and 1/10th's tend to be praking lot or rougher track developed, also remember a 1/8th is bigger and heavier and wider so it will be more stable at speeds and because of the wider chassis things can be mounrted lower making it more aerodynamic.