Got the PS1 version. Haven't actually beaten the game before, but a couple of months ago I decided to give it a go. I'm working on the Class 1 Golden era cup, but the 959 I have is really dodgy to deal with. If I'm careful, I wind up falling behind another 959 in the group. If I push it, the car gets really beaten up and I still get toward back of the pack. Luckily, because I got the 550 Spyder and the special race for it pays out pretty well, I think I've rendered money a non-issue. Still, I just need to push past this rut I'm in and I'm off to the Modern era.
Never played the PC version, but I've heard it's effectively an entirely different game.