Do it!!!
I saw it explained like this over on the UNI forum.
Say you were going to buy the express pass for the 4 adults and 1 child- how much would that cost? And the express passes you can purchase are only good 1 time on each ride. And staying at Royal Pacific, you will be 5 MINUTES away from IoA. The early entry is definitely a biggie. I hate to give much away, but even with early entry, on Friday morning we had a 35-40 minute wait for the Olivanders show. By the time the park opened to regular guests, I'm guessing the line was probably 1 1/2 to 2 hours. And did not get any smaller later in the day.
You will also be "ahead of the crowd". As you are leaving Hogwarts and going to other areas, the off-site guests will just be coming in. To Harry Potter, of course. So you will have a quiet stretch of an hour or so, when everyone else will be in one place and you will be somewhere different.
Do it!!!
My husband and I discussed if on a future trip if we were going to both Disney and Universal whether it would be worth it just to rent the room and maybe not even stay there!
I'm guessing you will have 1 day passes to IoA but if you have more than 1 day, you would have express privileges on the day you check in and check out.
Do it!!!
Easy for me to spend YOUR money, isn't it!!!