But we just got back from Universal and I must say I HATED their Express Pass! (From what I've read on these boards, I must be the only one in the world who does not love it, I know...) I have never waited in so many lines in my life. At Disney, our strategy was this: go early and ride mid-level rides SB during the first two hours. No lines. At mid-day, use a couple FP on headliners (no waits), see a show, and eat lunch. Skedaddle by 1:00 or 2:00 for a relaxing swim/break at hotel. Return in early evening to use additional headliner FP (no wait) and eat dinner. Late evening ride more low/mid-level rides, which would by then be walk-ons. This worked really well for us (at low crowd times) - we walked on to almost everything with no wait at all, and NEVER waited in line more than 10-15 minutes, that only on very rare occasions (Soarin' for example, where there is a bit of a wait even with FP). Granted, we are the type of people who like to do a variety of things throughout the day, not just ride three headliners over and over. This strategy worked really well for us.
At Universal, by contrast, it seemed we were always waiting in line, even with EP (which came with our hotel stay). Maybe we were just using the wrong strategy, but I'm not sure what else to do there.

Since EP is useless on the rides that actually have the longest lines, you've got no choice but rope drop SB. We waited 45 min and 20 min for Gringotts during Early Entry (for which we had to get up at 5:30 am Central Time

), and also explored HP world during the mornings since that was the only time you could breathe in there. By the time we got to the other rides at mid-morning, most had waits of 20-30 min or more. The actual wait time with EP was really unpredictable - one time (on Spidey) SB was listed at 20 min, and we actually waited 20 min in the Express line (basically everyone in line had express!), while another time it said SB was 30 and we waited 10. You just never knew what you were in for - but there was almost always a wait even with express.
Also, crowds didn't seem to thin out at all during the evening there, unlike at Disney, so evening touring was not much help. Possibly because Uni closes so early (8:00 during our trip - one day US even closed at 6:00!), so everybody sticks it out till the very end. Maybe also due to the older clientele there that stays up later.
It WAS nice to not have to schedule rides - I appreciated the flexibility and spontaneity of EP. But I personally would take any kind of FP over EP, since I am such a line wimp! I know I am probably the only one on here who thinks like that...