I also have PGR 4 (and Grid)....only started on Forza 4 yesterday, but enjoying it so far.
I rarely play for more than a couple of hours at a time, and use my boy's profile online....but I'm pretty competitive despite my.
Here's another oldish vid of me on Shift2. The AI can be pretty tough and agressive when set to 'hard', so you have to really make an effort.
My lap times have come down a few secs since I made these vids.
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