I like VC better for several things that always come up with stunts: 
  - a variety of camera angles for instant replays of stunts. 
  - slow motion for Unique Jumps. 
  - the camera looks forward with a touch of acceleration. 
  - graphics.  The SA graphics are often bleached out on the light end and muddy 
on the dark end and bland in-between compared to the rich hues of VC because 
they stretched the game engine too far for SA (for example, SA has a huge amount 
of water with practically nothing to see when you look in it).  The metal on SA 
bikes looks like unshaded colored paper. 
  http://img156.imageshack.us/img156/4161/00gta1screen83sh.jpg 
  http://img138.imageshack.us/img138/6255/00...screen8a8du.jpg 
  - the SA bikes feel like Nerf bikes.  You can turn around by ramming one into 
something.