DS3 gamepads have several untoggable driving assists that make the driving experience easier than with a wheels. Not only that, but lock-to-lock steering speed appears to be in some situations much faster than with a wheel. On the other side, you have a less precise control, especially on the throttle which seems to be handicapped on purpose (only 50% of the total range is usable).
Wheels with a total steering angle greater than 900 degrees (DFGT, DFP, etc) get a full, realistic driving experience.
Older wheels (for example 360 and 200 degrees ones) have some sort of steering assistance to cope up with their limited steering angle. This is tweaked (but never completely eliminated) with the arcade/professional/simulation setting in the wheel options.