The F430 is a better drive IMO. It's a more refined machine, and as with any decent Ferrari the chassis is just beautiful. You can't argue with that engine note either.
The Lambo is more extroverted, and the louder paint and interiors may appeal to some (not me though!). Also, 4WD means it could be seen as more practical. However, when will you be driving the car? In the snow and driving rain, or on sunny days when you can really enjoy it?
They're two very different beasts, and I'd be tempted to say the Fezza is the real driver's car here.
Get yourself one of these 'experience' days at a track and bag yourself a good test drive