I haven't played all of the metro games, but I can tell you that there is a LOT going on. Gas mask, filters, scarce ammo (etc.) I really enjoy playing, but in short bursts, an hour or two at a time. The stealth is decent, the combat is definitely intense, and the atmosphere is truly terrifying. This is a great game by all accounts, just a little overwhelming if you don't know what to expect going in, or if you're more of a casual gamer such as myself.
I don't really understand the hype over this game. The controls are trash! I can forgive the graphics due to the age of the game, but the controls for combat are a big bowl of steaming dog water!!! The cutscenes are unnecessarily long, like "geez, get to the point already!" its a solid 5 minutes AT LEAST before you even get to experience the swine feces that are the controls for this game! The story isn't even that great! This game is, without a doubt, HOT GARBAGE! If it were at all possible, I would give this game a NEGATIVE star review!