it is good to go in early with a RV, they don't put you in BFE. The first year we brought one we could watch the main stage from the roof and we went in early thursday morning. last year we waited and went in later and we were in the back of the RV lot. i would say with a RV the earlier the better, but thats just my experience. ;D
All the sort of khaki-colored campgrounds are the RV areas. I have no idea how they organize it though so I don't know exactly where you'd end up. I'm assuming 33 and 35 are the VIP RV areas, but that still leaves RV campgrounds in two other places where you could end up.