I used a wheel for several months back in GT5. FWD cars were the easiest to start with, since you didn't have to worry too much about the back end coming around, but that may no longer be the case, as a lot of FWD cars in GT7 have lift off oversteer for some reason.
The point is, start with some easy to drive, and get use to the wheel and pedals. As you get more comfortable, try something more difficult.
I for the most part enjoyed using a wheel, and was almost immediately faster in FWD cars, than I ever was with a controller, but didn't have a dedicated spot for a rig, and got tired up setting it up every time. I eventually went back to a controller, out of convenience, and been using one since.