Mass Effect is in many ways the perfect action RPG. It's a roleplaying game in the sense that you delve into your own character, build him or her as you wish, and act as you would in your character. The action is, according to some, just standing behind corners and popping out to shoot things ala Gears Of War, but I say you shouldn't be playing the game like that as it's boring. In combat, just like in story, ME gives you a lot of room to do your own thing. I personally just rush everything with a shotgun at hand and hope for the best. The story is also exceptional, as it is rather surprising although might lack originality on some parts. The "fight" between you and the main bad guy in the end can be fantastic depending on your character, which makes the game very reminiscent of Fallout 1.
10/10