The RTR has a few different parts, I believe it has plastic shock towers, doesnt have a CF radio upper tray, and just a few little things, nothing that really matters IMO

Id do a 8 or 9L over the VXL, that should be perfect for your speed, and run perfect!

Here was mine








Specs are

RCM EXT chassis, and goodies
LRP Sphere TC
Orion 10.5
TrakPower 2s lipo
2.2 truck bow ties
HB's LS10 wing, and T4 body