My highest use of miles if for WBC seats or UG's International. Bew 60K earlier this year for TATL ug's off an $880 B fare and was very happy. USed a lot of CO miles to take the family BF to Europe a few years bac.
Second best use summer vacation. Last two years have saved a couple of grant by using milies for the annula pilgramage to the west coast. Yes, the number of miles used is not the best milies/$'s ratio but sometimes when the choice is milies ( and you have them) vs 2K out of pocket the choice is easier.
This year was balt get FC in AS cheaper the NW or CO coach awards...Go figure...