I think handling in San Andreas is more realistic than in GTA IV. Let me explain.
Yes GTA IV have more realistic acceleration and brake forces (in comparsion to SA), cornering speed is lower, more realistic suspention on common cars. But, skidding In GTA IV is not realistic at all. Car is very controllable, you can steer easily while skidding - it changes direction like tank. Almost impossible to spin out. Very easy to end drift by counter-steering. If you played driving simulators you'll know it. As distinct from this, in San Andreas skidding is much more realistic, you'll feel that on powerful RWD cars. Understeer is there too, on FWD and 4WD cars. Maybe imression of more realism in IV come because it's more similar to your everyday driving. But in video game you drive extremely not like in real life.
P.S. I do multiplayer racing in both SA and IV and I'm good at it.
This post has been edited by Shortcot on Wednesday, May 16 2012, 01:37