I am testing it at the moment and I have to say you have done a really nice work, there are some things I saw:
That tuned sound for rx7s is just PERFECT. Love it.
I also like a lot your tuned sounds for the Cobalt and the Charger, as if they were engine swaped like in NFS Shift 2, brilliant idea
The Scion TC sounds and the Alfa Romeo tuned are nice too.
But, do you agree with the original sound of the R8 V10? It just sounds like the smaller V8 one. If you do, I respect that but I'm not fond of that sound hehe.
I also would change the sounds of the SLR 722, I would use "mer_cl55_a", but that's how I see it.
The Focus sounds a little bit too viper-ish for me, but I admit that it was a pain in the *** to find good sounds for it. I used "aud_r8_c_eng" and "aud_s4_a" and I'm still not happy with it.
Still, I appreciate your work mate, and I haven't finished testing the all the sounds yet. You have done much more than me in some weeks than what I've doing for months, and I respect that

. Keep up the good work! @