Wait till LFS tweak s2 is released, then you can have the XR_GTS that you want, just without the added "body mods" that the devs can do.
Personally, i don't want to see any more re-hash's of the old cars, im hoping for the "rally pack" and S3 to contain NEW car model's, not a bunch of remade S1/S2 car's.
Don't forget the sound. Thats the best part of the GTR/GPL games, they actually sound like they have an engine under the bonnet, and not a bunch of bees.