You get used to it - it irritated me after my initial excitement, because the controls are different enough to GTA:VC to warrant relearing and the car handling is more touch and go.
Give it a chance - I'm now becoming proficient with driving, having had to learn how to do it all over again.
The mouse combo with keys is fantastically brilliant once your used to it, it allows you to check around corners before you drive around them - basically to view 360 around you. It takes a lot of getting used to doing this while steering the car.
It does require a high-end video card - well, lets be fair, it requires a R1000 video card for a decent experience. Anything lower than a 6600 is not so lekker - playable, but with really crunchy graphics.
My biggest gripe is that I can't set radio stations by default to not play the gangsta rap cr@p - I tried to get used to it, but I just can't identify with the "nigga" "pimp" culture, possibly because I'm a 30something lilly-white english man - hmm, that may have something to do with it.
It's a different beast to GTA:VC.