One thing that is usually a good indicator of PPV buys is the Google numbers the day after the event. Rampage was the #1 searched for item on Sunday. After 172, Jones was #3, I think, maybe #2.
There was something else as well which I thought was incidental at the time but I'm starting to wonder now.
My TV isn't hooked up to a phone line so I actually have to call the cable company to order PPV. When I called, I got a message saying "Many customers are calling to order Bellator 120. If you are calling to order this event, please press 1". Now, I get this message for all UFC PPVs but I also order wrestling occasionally and I only have gotten this message for Wrestlemania and Royal Rumble. Other WWE shows range from 100K up to about 250K and there isn't even people ordering to trigger that message.
We'll see in a couple weeks. I hope that they did well because competition is good.