By far the BEST GTA game...
Graphics- The graphics in each game differ. On PS2, the graphics are still very good, but the engine makes some buildings and trees appear slower. On XBox, they're practically top notch, other than the loading screens, which are weird. The PC version has the best graphics probably. Everything loads right, the detail is great, and overall everything is so clear.
Missions- The missions in San Andreas are so much different than the ones in the other GTAs. For one, they are all a lot more detailed. They will take a lot longer, and involve more driving and killing, which helps to make them better than they already are. The storyline for them is very detailed in which the missions go along well with the story.
Gameplay- The gameplay is great! This is the ultimate "Do anything you want" game. You get a whole bunch of weapons to choose from, and running from the police is much easier in this one. The cheats make free-roaming easier and funner.
Overall, I suggest you definentely check out Grand Theft Auto: San Andreas.