Well tarey, you have a friend here! I must have played the demo around a hundred times. And the whole game like around 20-30 times!!!
I just said that it lacked replayability in the strictest sense, that being no MP support, which is generally considered to be a major component when replayability factor of a game is to be considerd.
I think it will be much better for him to try out both the game's demos and see what get's him, hook, line and sinker! That's what demo's are meant for! Personally, I will be rooting for Max Payne!