Even though lalathegreat is a demo racer, his point about setups is not as far off as some of you make it look, I think. The patch hasn't been out for too long and I think it's very well possible that further setup development might make the cars a little more even than they are now. I have to admit, I doubt that they will be as even as most of us would like them to be, but who knows.
I might be wrong here, but it seems to me that before the patch, the FXR had not been compatible for a very long time. It definitely wasn't for me. However, after some time (actually shortly before the new patch came out), I gave the FXR a new try and downloaded a setup from inferno (I think Flotch made it but am not quite sure). With that set I was actually faster on As National with the FXR than with the FZR. Of course, that doesn't count as much, as I'm far from being the fastest racer out there, but it seemed, that the FXR with the good setup suited my driving style a lot better. I wonder, if anybody else had a similar experience or if it was just me and maybe hope being the father of this idea (erm, I'm afraid that saying doesn't translate too well into english).