Only you would question if every single Metal Gear title in one box aside from the handheld titles is worth it. Come on, boo. It's worth it if you haven't bought the HD Collection, which doesn't include MG1 and 2.
I'd say it's worth it for MG2 alone if you haven't played it. It is entirely ahead of its time, and is basically MGS1 in 2d. Literally. It's even almost as cinematic.