I like driving all the TBO's all for different reasons...
RB4, is a little slow and boaty in standard form, but can handle like its on rails with the right set, but i have now lost that set, trying various combos offline in an attempt to make it again.
XRT, because RWD is fun, does take a little taming though, im not quite there yet, having fun trying and failing to keep it in a straight line on tighter tracks, SO town being a noteable example.
FXO, love driving this round westhill, very fast and pretty much easy to drive, although it does kill front tyres so quickly, this may of course be due to my 'turn the wheel further when i see a wall or something looming eventhough the front is clearly sliding' syndrome, i can see its sliding, the tyres are glowing orangy red in F9, yet i still steer even harder for some reason, i must learn to stop doing that.