We did EE at MGM the first week of June last year. We got there right at 8:00 and headed straight for ToT-- already a 20 minute wait, 3 minutes after opening! Afterword, we went to RnRC and the wait was well over 30 minutes already (don't remember excatly but it was more like 40-45 minutes) so we Fastpassed it. Did Star Tours and Muppetvision with no wait, then returned to RnRC to use our FP's. At about 11, the crowd became unbearably large. We hopped over to Epcot and ahd a much better time there. The next day, we went to MGM in the morning again. What a difference! The crowds weren't bad at all.
Personally, instead of EE I like to use the "morning after EE day" strategy...it seemed to work for us. The only exception is AK-- we do EE there to hit the highlights and then hop to another park to finish out the day.