In summer 2015 we will be at WDW for 4-5 days staying at WR. Plan one day at Universal. Is it worth it to change to a hotel closer to Universal?
It's not the proximity that's the issue. It's early entry (allowing access to Harry Potter both parks) and the unlimited express pass you get by staying on property at UOR.
This. Early Entry is available at all four Universal hotels. Universal Express is available at all but Cabana Bay.
You'll find the Universal hotels comparable to Disney's, at lower prices.