Metal gear 3 is my favourite, it's got the best combination of gameplay and story of them all. Probably the best boss fights of the series, so many good ones, I love the end and the fear. Fighting Volgen was great as a fight and he was a brilliant villain. The Boss was possibly the best bit, really escalated the game. 2 and 4 are both great. 4 felt like a good close to the series, though it had far too many cutscenes, I think it was more of a movie than a game. 5 was the best gameplay in the series by far though the story was unfinished and Quiet was silly, "You'll feel bad when you learn why she's practically naked". Bullshit just admit you want a sexy lady in your game that's still allowed.