As far as GRID goes, I loved it, that was the first game for me where I could use the instant replay function to learn the tracks, to see where did I make a mistake, then rewind and try the corner again. Also it was a great idea to bring so many series into one game, my favourites were the drifting and the touring cars, but all of them was pretty good, though a bit unrealistic. I really cant wait to try the new one.
I have the same problem with the F1 series, after driving more than 10.000 Km in the game, I have found the right setups for every track, and I have to put on primes in qualy, to give the legend AIs a chance, if I only qualify in the first two rows, I get them in the first corner. I just hope, they have developed better AIs for both of the new games.