I don't think the M1 guys would flourish, due to the ground and pound being heavily utilized these days. There are a few pure strikers in the UFC and Pride, but they all have great take down defense, and can usually survive on the ground if nothing else when forced there(the good ones anyway) until they can stand it back up. These days with more and more fans coming in, they are having the referees stand them up more and sooner to keep the action going. The best thing about that ElieXC was the 15 second rule....and the chick fight
The reason I like UFC better than Pride is the cage factor as well. You see a much better fight in my mind with the cage as opposed to the ropes.
I think the new breed of super well rounded, athletic styles are going to continue to change the pace and outcomes of these MMA fights.