Got some video of an SU-30 somewhere. This link isn't it but gives some idea of what the aircraft is capable of:
http://www.crazyaviation.com/movies/CA_SU-30.wmv
Anyway, the other piece of footage shows an AoA of roughly 120-130 degrees sustained for up to 10 seconds. It uses thrust vectoring and a whole lot of other fancy stuff including canards. It's not really relevant to the discussion at hand but it's worth watching anyway!
The one thing the Soviets got right was their aerodynamics. SU-27, MiG-29 and on were, and still are, far superior to anything the US had or has. Not sure how the F-22 etc. will compare.