Who has the best win in the MWC?

Utah State pulled of a huge upset this past weekend, going into BYU's stadium on national television against a ranked opponent and smashing the Cougars defense in a route. It was the biggest victory, in terms of defeating a big-time opponent, since the home victory over Utah two years ago. But was it the best win a MWC team has recorded this season? Here are a list of the top wins so far, in my opinion. Let me know which one you think was the best.

Nevada over Washington State, Week 2
Colorado State over Boston College, Week 4
Air Force over Boise State, Week 5
Boise State over Nevada, Week 6
Utah State over BYU, Week 6