I don't do the split-visit thing because when I go to US/IOA, I'm at US/IOA. And when I go to WDW, I'm at WDW.
That being said, if you want better rides, you gotta go to US. I'm a Disney freak, but my best ride in any theme park on the planet is ROTM. There simply is no queue better (OK, except for HP, of course!

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