I don't really like the 2 mods, maybe the Porsche a little bit. But I like those default cars better. Now choosing from them is hard! I really like the Minis, the Caterhams, and I think I would like the Formula BMW-s too, just I had only 1 race here in those! And so that is the class that I would like to race from these the most! (so I voted for them)
Formula Master and Radicals are also pretty good, I like them (in this order).
The question however, "what are your favorite Race mods", brought the Escorts to my mind. Generally I like the default cars better, but if I had to pick a mod to play with, that would be those! Extreme fun!