I haven't played MP just yet as I want to beat the SP game first. I've loved the Demo's and I'm 2/5 to 3/5 done with the SP and still love it. Comes down to taste obvisously, but this reminds me of Doom 2 with it's dark atmosphere and eerie ambient sound effects and throw in some 'minor' Serious Sam influence in some rooms and for me, at least, it's a dam fun game. It's a nice change of pace to laugh once and while while playing a game.