Thanks both, discussion like this always good to follow - for sure everyone has their own things that break immersion so it's different from one to another.
Thanks for Snetterton in particular Rainmaker, I think this one works particularly well without too many objects directly trackside to give the 'cardboard' feeling away. And boy wasn't this a better circuit without the modern interior loop that British GT will be running this weekend! The ACC version might be better quality but boy is it a less fun track to drive.
My personal immersion breakers for this one are the repetition of crowd and bush textures; always gets me when the crowd texture loop is so obvious.
Other point on this one but the AI is really slow - they don't venture into the tarmac 'run off' areas at all, so even at 100% I'm frequently 3 seconds faster than them (and I'm far from being an 'alien'!). I'll try to have a play at creating one when I get a chance.
Anyway, thanks for the updates and for the continual improvements to them, much appreciated.