No way was this ever marketed or meant to be competition for Assetto or iRacing. But I think it's quite a few steps away from GRID2. I'll give you a for instance...
I got on and immediately went to the IndyCar. I could not believe how floaty and slippery it was. Then, I started tinkering. I'm sure if I can tinker, you computer guys can tinker much more.
My problem was lack of FF, not to much. So I had to dial it way up to 90% on the Fanatec CSR and 100% on the game, both settings. I have a separate setting on my wheel that will amplify environmental effects. But it sounds like you feel them plenty good. That bodes well for the Madcatz and MS wheel users. I talked to a Madcatz user today who was very happy. I have two settings on my wheel pre-mapped. One for touring and one for open wheel.
The touring and open wheel Sen (rotation) are set to "off" and it works perfectly. Another good sign for MC Wheel users. In fact, the preset says "Microsoft Wireless Wheel" With my wheel, and open wheel, I had to really get into the crux of the handling. To me, the biggest problem that remains (and only problem), is the brakes. With ABS off, you are going to lock up no matter what you try, unless you have a super expensive set. I just turn ABS on. I'm not too proud. I does not hurt the lap times all that much. In addition, I had to get rid of that float, and that was accomplished by the Sen setting, but also dRi and SPr settings. The first allows you to correct mistakes more quickly. It was meant for drift, but comes in handy when you want to smooth out the path of the car. That in combination with the Spr, which allows the wheel to "snap back" to center more easily was a huge improvement in the handling of the IndyCar. And just like F1 2012, you have to go to extremes with tuning. Max Downforce, Max Diff to open, and almost full left springs (very soft). Combine all of this and you have an open wheel car that rivals F1. Of course they screwed up the pits and of course they screwed up the fact that these cars will flip the moment they hit sand, but they also have flashbacks and the damage doesn't kill your ability to compete unless it's red. I suspect the F1 crowd and the PC crowd will say it's not up to their standards.
Of course, the A.I. and the graphics for us console people are outstanding. I have never experienced more intelligent A.I. Sure they are a bit bold, but so are real racers. You have to work to pass them and they will pass you when you are not looking (well, that's another conversation...mirrors...hope we get them).
If you keep the races short and clean, you can have some good ones in open wheel. Just give a flashback or two (nothing more than a pit stop on the track), and you can have a great race online with the right people. N, it's not the same "feel" as F1 2013, but I would argue that F1 is almost too planted, too sterile, too smooth, and too much like driving a car that is radio controlled instead of trying to feel what it's like to be in there.
And I think they nailed the touring cars. Maybe among Categories they are similar feeling, but not across Tiers. They are very well thought out and so much fun to drive. That is where the game really shines.