I've never done the either park (but I'm finally going to do one this next trip!) so I can't answer which is better, but I'm trying to figure out why you'd want to attempt this. You can't park hop between water parks so you either are paying for two admissions or using two plusses. If you feel like spending a whole day at the water park, it would make more sense financially just to stay at one park the whole day. The water parks are generally open 10-5/6, so I'm sure you could do 3-4 hours in one and 3-4 in the other if you really wanted to.