I don't even look at it as being a contest; CoD is a good series but the constant run-and-gun is tired and over-played. Sure, the same comment could be made about RPGs like Mass Effect, but there is much more to Mass Effect substance-wise.

You should purchase Mass Effect - you'll get your money's worth out of it. CoD4, sure it has multiplayer, but I'm sure you're already gunning it up on Halo 3 or something like that on multiplayer - so is it really that big a bargain?

Another thing (sorry to go on a tangent) but if that is the only thing that sells you on a game anyways is the multiplayer, then that's a sad purchase anyways - because that means that developers didn't have to go through all the trouble to create an impressive storyline and great effects, graphics, dialogue, and the like if all one was going to do was ignore all that and frag people until they're blue in the face.

I mean, Mass Effect looks to me like Half-Life and Half-Life 2, the reason I say that is because when those games came out - people said "wow, that's really innovative" but for games recently like Halo 3, yeah, there was hype and fanfaire but was the game really that impressive as far as leaps in technological advancement? I would say no.

But for Mass Effect I would say that it is a good game with so much to offer that I think you would get bored by just running around and shooting people like in CoD4.