We just got back from a trip to VWL, and we were happy with the transportation system.
The boat to MK is a very nice ride....go in the back which is open and just bask in the sun and nice breeze. Everywhere else is a bus ride.
I will say that the bus to Animal Kingdom was a fairly lengthy experience. We got picked up and it stopped at Fort Wilderness and Blizzard Beach before getting to the AK. All told, it was a good 35 minutes from pick up to arrival at AK. And then, coming back was done in exact reverse! I had hoped that it was a loop but evidently it was more like moving from one end of a path and back along the same path. But still no big deal.
I must say that if someone is the type to pat their foot impatiently and thinks a 15-20 minute wait for buses is a real pain, then they should prepared for a little anxiety. Most of our bus waits were less than 10 minutes, the longest was about 20 minutes. We found that to be very acceptable but if you're used to walking out the door and being in a park in 10 minutes, this may be more laid back than you want.
Just don't want to sugarcoat the transportation system. We love it and use it all the time, but some folks hate waiting at all.