Camera performance is definitely comparable. If you install apps like LG Camera or Camera Zoom FX, you can get even better image quality. So, the negligible difference in quality will not even be noticeable (installing Bravia engine hack boosts quality of image even further, though only on the mobile screen, because it is a screen hack, not a camera hack.)
I wanted to post results of testing various kernels on CM7.
Ratings for various kernels:
1. Stock CM7 kernel: Performance 8/10, Battery 8/10
2. IronKrnL 1.3GHz: Performance 8.5/10, Battery 8/10
3. IronKrnL 1.5 GHz: Performance 10/10, Battery 6/10
4. Vadonka's kernel (normal version): Performance 9/10, Battery 8/10
5. Vadonka's kernel (powersaver undervolted version): Performance 7/10, Battery 9/10
All kernels above, except first(stock CM7) which were tested had 32MB RAM hack, and included voodoo sound (voodoo sound doesnt affect performance, only audio quality), and Sony Bravia Engine hack(no affect in performance again, only image quality).
Other popular kernels include:
1.Horsepower extreme (only for stock ROMs, so could not test)
2.Blazing dragon (only for stock ROMs, so could not test)
3.Vorkkernel (not updated since 16th Nov, so not tested)