I have owned Sm ( original red version) twice and it is a really cool game that I will one day own again. I prefer the original SM over the vault by a mile, although the vault does have excellent animations in the display that are superior to the original.
I have also owned X-men pro which I sold and regretted but once I got a chance to buy a 2nd hand Xmen LE I jumped on it and it will never leave. X-men LE is one of my favourite games ever made and as others have said it is highly underrated.