You could just get a throw away one night reservation that covers check and check out day for around $500 and get Express Pass for free with your “stay” at HRH, POB or RPR.
1/2 the price of buying separately.
I did look at that option. $600 inc taxes, etc. Still seems darn steep just for one day express passes. If we were going to stay in the room and do two days at the park, we would totally do that. Our debate is go to Universal without XP, add a day at Disney for AK, or maybe to the Disney water park. We have been to Disney several times before, including the water park.