Quote from uttoro :

The XRG. The most realistic car in LFS.

XRG is my favourite too. Most realistic, most fun.

FZ50 is my favourite, tough car to keep it straight at corners, it's fun.

GTT or XRR

Now GTT is even more funny than s1!!

And XRR is its race version, hehe

The FXO GTR can be a lot of fun, mainly because it's so big and stable you can really throw it into corners without having to worry.

Nothing beats the four speed fury of the UF1000 though.

Quote from mrodgers :

FZR all the way. Love the way it screams to 9-10,000 rpm.

I don't think that any car in LFS really literally "screams" because of the generated sounds.