I absolutely love the wagon! Lots of room! I can stand up in it (I am 5' 5"). The power seats are extremely comfortable, and the view is great. I posted some pictures in the 'delivery of custom transit' thread and will attach a few here. I had a few concerns before I ordered it - wasn't sure if there would be enough cargo room with the 10 person seating, and wondered if I should have ordered a 148" wheelbase model. I am extremely happy with my choice, and glad that I didn't go bigger. It will be my daily driver, and it fits (barely) in standard-length parking spots. If it was any longer, my choice of spots would be much less (in areas I frequently park in). The medium roof is so high I can't really imagine what the high roof would be like.
There is more cargo room behind the last row of seats than there was in my Odyssey. If I have anything big and bulky, it can go in the large area beside the sliding door.
Seating is a bit tight, but my people are still pretty small. I can sit in all of the seats comfortably. My 6'3" husband is more limited, but there are still lots of options for seating, including lots of aisle seats. I was going to take out a couple of seats to provide more legroom, but it is fine for us. I am going to leave all the seats so they are there and available if needed as I don't feel that it is necessary to adjust the seating positions. If I had all 6 foot plus teenagers I would take out a couple of seats (probably then I would take out the back row and move the third-row 2 person seat to the back. I would go from 10 seats to 7, but almost all would have amazing legroom.
The door is heavy, and my kids are barely able to close it alone (but are able to - youngest two are 8-9 year-old sized). Also, we have the step and it is fine for the sliding door, but front doors could really use steps too. I can manage, but it is a big step up to the cab. My similarly-sized 12 year old son with some special needs is having trouble stepping up to the front passenger seating position, and more trouble stepping down as he doesn't want to back down. We will probably end up adding a step at some point.