Just as GameSpot says: extremely entertaining and varied game play that shouldn't be missed.

User Rating: 9.5 | Grand Theft Auto: San Andreas PC
Good: fast loading times; variety of missions in the main story (e.g. incorporates stealth, 'hitman'-like, flying, and assault missions, plus many, many more); great dialogue and interesting characters; great story and plot twists; large and immersive city; TONS of vehicles to drive (from monster trucks to Go Karts to jets to sand buggies to quads to jetpacks, the list goes on); allows you to play your own music on a dedicated radio station; although the music on the radio stations is somewhat older, it still is very enjoyable while flying your jet or riding through the countryside, for example (it kind of just "fits" the game play); variety of surroundings (city, suburbs, Chinatown, Vegas, countryside, etc); cool "gang-element" (allows you to fight for and defend your 'turf', fight with rival gangs, recruit members, spray paint gang graffiti, etc.); LOTS of depth to the game (going to the gym to build up strength and stamina, buying real estate for safe houses, etc.); some fun side missions (e.g. BMX challenges); lots of customization (e.g. outfits, tattoos, haircuts, etc.); allows you to take snapshots with a camera that save as screenshots on your PC; variety of weapons to use

Bad: sub-missions (not related to story, but count toward 100% completion) are mostly repetitive and VERY frustrating at times; police AI are WAY too smart (they obviously get more relentless as stars go up, but even at star one or two they can get very annoying): coming from anywhere, running up out of nowhere, a little too numerous (one walking down every other block), etc; all the safe houses look very similar; story starts out a little slow; no game pad support; you lose weapons when you die (not just when being taken down by cops); vehicles automatically catch fire and explode once they land upside down (forces you to run away as fast as possible, gets annoying after a while); map does not show how to get to a destination, just where it is: takes some navigation and map reading skills); low quality graphics textures; gang AI are semi-retarded

Overall: GTA IV was the first GTA game I ever played. I thought it was a great game, but I heard many people arguing that SA was more fun. I decided to try this game out and I'm glad I did. SA definitely has more depth to it and offers a lot more than GTA IV does. Not that GTA IV is bad, but compared to SA, it easily shows where it lacks. GTA: SA is one game ANYONE should try, especially those who enjoyed GTA IV. There's just no describing the immersion this game offers.