Exactly as stated above, Business Travel is the only logical use for SWUs. I pay about $2,500 for a Y, B or M fare to Europe a few times a year instead of $6,000-8,000 in Business. I NEVER book online, and always get the upgrade confirmed by an agent before purchasing the ticket. Despite the hassle, I then go to the Airport PRIOR to the flight, and physically hand over the coupon and get the ticket re-issued in Business. Pain in the @rse - yes, ever been disappointed on the day of travel - no. Convenience factor for a FF freebie - Zero.