Good, but not great, For fans of GTA series, you will find lots of new things to do. However, I liked GTA:VC better.

User Rating: 7.8 | Grand Theft Auto: San Andreas PC
GTA:SA is big, and the amount of things you could do compared to previous GTA games will keep you exploring the game. The game can be played on a quite a low end computer which is an advantage as the GTA series graphics are pretty average.
The game provides a a set of missions but you do not have to follow them, and lots of "side missions" such as getting a new haircut, new clothes, going to Gym and the chatting up the GF etc, which gets a boring after a while. However it is the hidden mini games, the different things you can do which makes the GTA series so great. The sound it OK, and don't expect much. The radio was not as good as GTA:VC (I just cracked up at the radio shows on VC). The language is mature, but that just adds to the atmosphere.
Having said that, I liked GTA:VC better, maybe because I grew up in the Miami Vice era. I also found some of the flight missions pretty tedious (not being a simulation person), which spoilt the fun for me.
If you expect a blind FPS you will be disappointed, as the GTA series is more an action adventure with some FPS elements. It's not all out action, but all out fun.
Overall it is an excellent game, and still highly recommended.