We just did this exact trip. We had an extra day and planned to take a day off to rest in the middle. Because we arrived later than we planned in the day and didn't accomplish what we wanted on our first day, we upgraded to a 6 day. (also, if you decide to do this PM me, let me give you advice, I had a very hard time getting this done, 2 CM's tried to charge me almost 100 extra dollars - a SUPER CM took over, shortly before my nervous breakdown, and we got it taken care of - so please PM me for advice) Anyhoo, we added the day and I will regret it until my dying day!! The day before our "added" day, we were in MK from opening to closing, and we made it just fine, and had a great day, but that next day, even though we slept late, and went to the park around lunch, we were miserable. We wasted 240 bucks on that day, and I mean wasted. We were so tired, snappy, and just plain give out. We went back to the room early, swam and went to bed. We had better days the rest of the week, but we were still tired. I will always wonder what kind of week we would have had if we'd just rested all day. PLEASE REST. I thought we'd be fine, I was wrong. I like the EPCOT on the first day idea. My
travel agent suggested epcot first because after all the magic of everywhere else, epcot may be boring, but first it would be cool. (although mission space could NEVER be boring - my favorite of the trip!!! Thumbs up!!) Have a great time. Wish I could be there!!