I like the less travelled path generally and to stick out, I try and go for cars that few people drive. You have much more individuality by using cars that aren't seen in every single race.
Suzuka 500PP believe it or not... the lame Delta Integrale. Slow as a wet week, stuff-all grip, understeers like a bobsled, but hey, it's great fun.
Suzuka 600PP - I'm a fan of the Jaguar XK - it is one of the hottest looking cars around at the moment and just so sleek and pretty that I can't go past it. Mind you it's far from a quick car, it has way too much weight and not quite enough power to make it work the way I want, so I tend to get eaten by quicker drivers through the twisty stuff. The Jag does really well into turn one, is great fun through the degnas, handles the hairpin reasonably well and doesn't do too bad through spoon. It's very stable through 130R and although the brakes aren't the best, you can fling it through the final chicane with reasonable gusto. but through the esses, the car loses miles and this is where it really hurts.
The other car I've taken a liking to is the classic 512BB. Nice lines, brilliant aerodynamics and will happily crack 150mph down the back straight and the main straight too, but you can't fling it through the high speed stuff with disrespect as it tends to pendulum away from you pretty quick. The Ferrari gets hairy coming out of Spoon, doesn't like the kink approach into the hairpin at all. Throw it through Casio with too much force and you'll end up with your exhaust pipes where your nose should be, hehe.
I've been considering the Lexus IS-F, but that may be too easy, so what I'd really love to do is get a Mustang GT together so that it's competitive. That may very well be asking the impossible though, hehe!