One more time of me chiming in on what a fan I am of this perk:
Have a trip to London in February for work. JFK-LHR weekend to weekend route. Used SWUs both ways. Was only a 550ish fare, so saved the company money, meanwhile am flying in biz class both ways, which takes the sting out of traveling on a weekend for work.
Very happy. Thanks Hyatt! Thanks AA!