I'm playing it on 360 and having no problem with frame-rate. Was perfect. Just raced Monaco and didn't notice any problems. Graphics are amazing.
It is much more realistic. The top teams are way faster. Although I do agree with the person who said it's too easy to take places on the start / first corner. It's as if AI doesn't use KERS at the start.
KERS and DRS is very cool. You even get random failures of DRS and KERS. Which is cool and annoying
It takes a lot to get a penalty. I smashed into Vettel on the Spanish GP after mistiming my braking, didn't get a single penalty.
There are no press-conferences which is annoying. Loading times are longer.
Handling is just amazingggg!! So much better, takes a long time to get used to.
Best finish I have had is 5th and that's on Professional AI. It's very very hard to win and much more realistic. I'm playing with Force India.
Also the tyres, you really feel the different between temperatures.
There is great attention to detail.