We have done Disney transportation as well as private transportation. What we liked about Disney transportation was that you loaded onto a
Disney Cruise Line bus, decorated with porthole windows and Disney characters. They played Disney shorts to keep you entertained and as you got closer to the port, they played a short information film about the ship and all the things you could do on it. It keep you in the 'Disney' bubble and builds on the excitement.
Having said that, we just cruised Feb. 25th and took the
DCL transportation from our resort. What showed up was a fairly beat up coach bus with no Disney anything about it. They showed a bunch of Disney short cartoons on repeat, by the time we arrived at the port we had seen them each 3 times, some 4 times. There was no information about the ship. It was the most disappointment I had through our whole vacation. There were 7 of us, 2 had never cruised DCL, and had I know what we were going to get I would have booked private transfers. It was a big let down.
I'm sure some DCL buses still pick up from the resorts however don't just expect it like I did or you could be let down.