Yeah, I've driven in the Nice area. The roads can be very wind-ey and congested at times.

Having said that, the roads between Nice and the Italian border can be fun to drive at the right times. We usually go in September/October, and the rest of France has gone back to work, so congestion is down.

I would think a convertible (cabriolet) would be a ton of fun without incurring outrageous fuel costs and the constant fear of getting dinged by some Vespa who didn't see you because you're too low to the ground.