If you still haven't played this game then you should start cursing yourself.
Kudos to Rockstar for making such a wonderful game that left it's predecessor behind many a mile.
Added feature here is that you get to play so many vehicles like Bikes, Boats, Helicopters [including that of the military], etc. which were not available in the previous versions. Though this game is individual in it's own right & not a sequel to any.
There are awful lots of missions to complete which includes Hidden Packages, Unique Jumps, Import/Export Cars, etc. which will keep your interest in this game for hours.
Apart from all this another major & great part of this game is it's storyline which is quite solid & for which GTA is well known.
The twist in the game in the form of betrayal was expected but nevertheless good.
Nice graphics giving a feel of the 80's.
Voices of characters is also well portrayed & sounds of bikes, boats, choppers, etc. are very realistic.
So should I go for this game?
Ofcourse. What are you waiting for. It's a complete package.
The Good : Great Storyline. Low system requirements. Robust gameplay.
The Bad : Saving the game at certain locations has a bug which will corrupt your entire save file. So make more than one save files.
Final Verdict : A must have game. Highly Recommended.