This deserves a big X over the box to warn you not to buy it.
You have a good selection of characters to choose from, but the game goes downhill from there. It has little to offer as compared to the Mortal Kombat and Street Fighter series. There are also many more X-men games out there that are so much better for an X-men fix. There are even better X-men fighting games. While the graphics are a little cleaner overall, it doesn't mean that they are any better. It doesn't have cartoony look that many of the other versions have. I think that the cartoon-style of graphics are better.
Just go to the arcade for an X-men fix or look to the PS2 for a better version.