My nephews have this for the Wii. I played it a few times with them. I doubt there is any difference between the consoles. Maybe better graphics? The Wii was horrible, but what is expected?
The figures can get a bit pricey, especially the bigger ones. As long as you have the code cards for the figure they should be good to go. And you might need to reset the characters level in the menu because the person that sold it could have it max level, then your son wouldn't have anything to work on.
My niece has Disney Infinity and that's like the same thing, just Disney.