They are NOT limiting to 3 or 4 a day. They have available "short term" cups that can be used for up to 4 fills within an hour. The mugs are unlimited fills for the length they are purchased for, just with a 2-2.5 minute limit between fills. The water parks have a similar system, but it is for daily use. They do offer to "re-enable" previous mugs though. I believe the price of the mug is similar to the 1-day mugs at the resorts, but I think the mug itself is bigger.