well..i recently bought a ps2 with nba street as my only game for the time being...and i have been extremely happy with it...its the best bball game ive ever played as far as realism, graphics, and gameplay...you will have lots of fun with this game for a looong time...and there are tons of things to unlock, plus challenging friends will lead to hours of war....
..my next game coincidently will be klonoa 2, however my friend bought it last week and finished it within a few days....
so if youre looking to invest in a game that will last you for a while...(although theyre both phenominal games) id put my money on nba street....