I've only played the original PlayStation 2 release, but wasn't the PS2 release of Metal Gear Solid 2: Substance the version with the most content? I'd take a leak of that one over the other versions.
I think the only extra feature it has is the skating mini game. Now the og release of MGS2 US was interesting for the differences it has compared to even the JP release. US came first and is almost a kind of beta version.