I find EA MMA by far superior to Undisputed. It's much more fluid and it doesn't include button mashing. The controls are great once you get used to them and the Create-a-Fighter gives you almost unlimited possibilities INCLUDING names and nicknames of UFC fighters (and the ring announcer even says the name). The submission system requires some strategizing especially against human opponents and it doesn't rely on button mashing or "shining" at all. There's a variety of styles in the game, and also sub-styles. For example you can build a BJJ whiz who is especially good at leg locks or an actual counter striker (meaning counter striking is actually possible in this game). That's because you have so many stats like hand speed, left hand strength, right hand strength (I guess you get the idea). It has unified rules, DREAM rules and vale tudo, octagon and a ring and did I mention it doesn't use button mashing at all? I don't think I have. Blocking transitions actually involves you pressing a button instead of "3 blocks max and then he passes your guard". Did I mention you don't have to rotate your controller stick a lot?
Wow, this turned out to be a minor wall of text.