MGS2 snake was the worst design costume wise
That award has to go to Portable Ops where he's wearing those bizarre stockings.
I believe his sneaking suit in MGS2 is the same one from MGS1 but without the padded vest. Honestly I think every new iteration of Snake has been an improvement over the last, Yoji Shinkawa never ceases to impress. Even the design of shirtless Snake in MGSV seems to have had an absurd amount of thought put into it.
I'm also glad they finally ditched the bandana, it was getting a bit old.