In all honesty I wouldn't go to Universal or IOA without the hotel room key to get me to the front of the line! On the 8th (our first night there from Disney) we went to Universal. We got in line for the Mummy, got just about 4 steps away from entering the actual ride and it was closed down for technical difficulties. If I had to wait in a 60 minute line I would really have been ticked off! We waited 8 minutes before this happened. Additionally, we went from the mummy to MIB my 10 year old and I were actually next to board the ride when again it was shut down for technical difficulties. At this point I'm steaming mad and ready to have a fit. Hubby calmed me down and we went to get a bite to eat. After that we tried MIB again, once again 1/2 way through the line they stop it for technical difficulties. That park is so lucky that I didn't have to wait in those ridiculously long lines or I would have exploded right on the spot! Then they would have really had to shut down for technical difficulties while they mopped up the mess my exploding head made!!! We chalked it up as a bad day, went back to the Hard Rock, started again early in the morning to try again. The rest of our trip was amazing. That first day we got a later start at the park and I attributed the TD's as wear and tear from a day of running, however I heard rumor through the hotel pool gossip vine that the actual problem was certain individuals exiting their cars on MIB which caused the shut down. Don't know if there was any truth to that but that's what I heard. I guess everyone has a bad day once in a while, and even though I was ticked off I got over it the next day when all went well and I easily rode everything I wanted to at least twice.
I wouldn't spend the money for the express pass you purchase. As you mentioned you only get to ride each attraction that has express pass once, not worth it to me.