Something tells me that DU will beat WMU. I would be very surprised to see DU exit in the 1st round for a third straight season...
Especially with how well they played on Saturday against UND.
I think a DU/UND rematch (should UND beat RPI, of course) would be a toss-up. I still think that UND hasn't played their best hockey yet against DU, and if they did they should be able to beat them. But anything is possible in a one and done.