I also have LFS and rFactor.
My opinion is that rFactor has a weird kind of understeer feeling (maybe its just me), but with default setup it feels like that. Also when taking corners it sounds like its scraping.
The thing i do like about rFactor is the incar sound..
I feel more connected to LFS with driving, tho the sounds are plain and graphics basic (if you compare it to nowadays graphics available) but i like the LFS physics more.