Manhunt is a brill game. It rocks, but you must not confuse it for a run and gun action game like Vice City. It is worth getting, I had never played it and only read reviews, but I got it for Christmas and I was not disappointed. I don't think the game is too short either, there are twenty levels and I still haven't finished it. I've played about 15 hours and I'm only up to level 12 (I think?). It takes this long because I kept dying, some parts are that hard.
The game is really gruesome and if you can stand things like shattered skulls and spilling brains onto the ground then this game is for you. Just be prepared to die more than a few times. The game has a really neat graphical style, it is very gritty and realistic. The game is scary because of it's realism, just imagine some White Supremist members chasing you down, with baseball bats and nail guns, shouting at you and taunting you. It's pretty freaky.
I recommend this game if you own a PS2, and have the stomach to witness some of the most disgusting death sequences to grace a console. Buy it now!