I've been to Gay Days Disney and it's a blast. You get the hotel and its amenities all to yourself, and if you go FOR SURE go to the waterpark night (if they still have it).

Vegas isn't a very fun gay destination in the first place, and the opportunity to go to a mediocre theme park and a drag show you can see anytime doesn't seem to add much. It would help if they could reserve some common areas, like the pool, so people could socialize.