If you want to talk the most recent, Extreme Rules didn't even got 200,000 PPV buys (source: http://impactwrestling.com/Content.aspx?ID=32753) whereas the two UFC events surrounded Extreme Rules, UFC 112 and UFC 113 both DOUBLED that and more with over 500,000 PPV buys each (source: http://www.mmaforreal.com/2010/4/15/1423759/meltzer-ufc-112-a-major-ppv-success and http://www.mmamania.com/2010/5/24/1485627/ufc-113-early-reports-suggest)
You have evidence of the statistics, and you can't get more modern except for Over the Limit, whose buy rates I couldn't find online in my brief search.
UFC ppv > WWE ppv
You have evidence of the statistics, and you can't get more modern except for Over the Limit, whose buy rates I couldn't find online in my brief search.
UFC ppv > WWE ppv