The rotation is fully adjustable when attached to the PC. When on the PS3 the game controls it and it does a very good job of it. Some cars have tight steering like the karts, the F1s and the X1 and others are looser. None that I have seen use the full 900 degrees more like 360 or so which is actually less than a real car would have so if this is to much maybe you should use a controller.
Yes the Fanatec has awesome FFB. Enough to hurt you at times. It is reccommended that you set the rotation adjustment to OFF for GT5 which allows GT5 to contolr the wheel and get get the exact same amount of rotation as you would with the DFGT which is how the game is intended to be played.
My DFGT came yesterday. Of coarse I have to get used to it, but I must say it's a fine wheel. I don't miss the adjustable angle, GT5 does a good job the way it uses the wheel. I do find the dead zone too much at times, but it seems it depends alot what car your driving. With dead zone a mean the spot in the center where the FFB doesn't seem to be present. The wheel DOES steer precisely in this spot, it's like a spot where suddenly the FFB is gone, no resistence, kind of wobbly feel.
Second the FFB is kind of grainy, not smooth, I think this is the motor itself thats strugling to turn against the human force.
In my opinion the wheel is capable of doing it's job well, it's the software (GT5) that should have more adjustable settings, so you can do more fine-tuning, like adjusting the dead zone, and dampening.
I prefer GT5 adjusting the wheel for you, so it gives a different feel to each car you drive, above a fixed setting like the Fanatecs, even though you can have 5 settings in memory. As I said, GT5 only should have more fine-tuning posabilities, that would really make it a best buy for the buck.