[Gelatoni]

I've visited 3x now, and have always done the same because of the way the tickets work: 3 days, first 2 one park only, 3rd day park hopper. I think that's the only way you can do it properly as you will definitely want to go back and do anything you missed, as well as some of the incredible rides you'll want to repeat.

Given the long queues, it's quite likely that you might miss something the first time around and make it a priority for the park hopper day.

I'd find cramming both parks into 2 days exhausting.