The biggest difference between the standard VoneR-VoneS rear end and the VoneRR floating rear end isn't the position of the body mounts, but the angle of the shocks (lay down more with the VoneRR mounts)
On my cars I found that the car had both better traction coming out of tight corners and rotated better entering corners, and I tried the rear mount on both my VoneS and my VoneRR
Lue