I did a couple more races earlier, and really not sure what to think of the game now.
The physics/handling in terms of a single car are reasonably good, not proper pc sim level but good nonetheless.
However in terms of collisions between 2 cars I'm not so impressed, you can clobber other cars far harder than I think should be possible with no real effects on either car, I almost feel as if this has been 'dumbed down' to appeal to a greater market...
Then there is the AI, in some aspects they're good, although they still make silly 'mistakes' like turning in on you, but it's hard to code a really good ai, so I'll let them off that.
What disappoints me is the speed of the AI, even on 'Hard' they're fairly slow, I won a Mini race by something like 7 seconds, and it was only in the last corner of the first lap that I gained the lead.
I can imagine the hotlapping/leaderboards being fun, and maybe the online racing if you find a good bunch to race against, but the actual single player I can imagine being a chore...