I've seen conflicting information on this, but my understanding is that they'll only transfer luggage from a Premier hotel. They'll transfer it to any hotel on property, but you need to be going from a Premier hotel to get this service. I'd need to know more about the logistics to have a firm opinion, but if I'm Universal I think I'd prefer to provide the service if it means guests are going to go spend more time in my expensive theme parks rather than using that time to schlepp their bags to another hotel.