Did this last December and doing it again next June. It's really great. We weren't planning on doing the MCO thing originally, but when I figured out how convenient it would be (and got a Hyatt credit card so I had a free night coming to me anyway), I changed flights to the evening before our Disney check-in. I called Magical Express to see if there was anything I needed to do, and the person there said nope, they don't really care when you flew in. As long as you have a resort reservation beginning on the day of your Magical Express reservation, you're golden. So we got into MCO around 8:00pm on a Saturday night, checked into the Hyatt, went and found some dinner (Italian place in the airport, forget the name, but it was good!), then went back to the Hyatt and hit the hay. Got up bright and early the next morning, got dressed, packed up, and went down to the Magical Express. We were the ONLY people in line when we got there, and about three or four others (maybe two families?) joined us in a few minutes. We got on our bus, I think one other family was on there, and were at the Grand Floridian by a little after 9:00 am. We dropped bags with bell services and were going to head to Epcot, but we were checking out the Grand's decorations and getting pictures taken in front of the tree when I got a text that our room was ready. Got bags, took them to the room, then went and got on the monorail and headed to Epcot. Spent a few hours there, then came back, rested, changed, got something to eat, and headed to Mickey's Very Merry Christmas Party for the night. Had we flown in that morning, there's no way we would have had the time and/or energy to do all we did that first day. From now on, flying in the night before and staying at the Hyatt MCO is always the plan!