MGS3, we love u!
MGS3 turns out to be my favorite of all the MGS games, even though it is not a technical achievement like MGS4 and was not hyped up as much as MGS2, the reason i like this game is that it is by far the most emotionally driven of the series and is just all round a fantastic story, and one that you cant help but feel sorry for Naked snake (AKA big boss) throughout, by far the most down to earth of all the metal gears.
Plus the whole basic survival aspects of the game are just a pure joy to play as you do honestly get a feel of survival is key, and the bosses are as usual completely absurd but still fun to play against, even with the very choice camera view that you have to play with through the majority of this game.
All in all MGS3 from a story perspective is by far the most involving, and die hard fans will love it even if you did play MGS4 first, it will never be as good as this!