When they're in cars, they seriously suck. Super ramming (cop cars in this game are slow as sh*t, so I don't know where this comes from), they don't follow any laws of physics whatsoever (A truck doesn't do anything when side slamming a cop car. Really?), and the rolling road block is robotically orchestrated.
Cop chases in GTA used to be really fun. Now they're just annoying.