We always get a rental car for our trips. I'd rather be in control of my own transportation than relying on someone else. I like being able to go to my rental car instead of waiting in another line to catch a bus at the end of a long day.
But we also use the car after the Disney portion of the trip to head to the Gulf Side beaches.
The one day I needed to get to DHS with my son for the Jedi Training Academy so I took the car with him and my DW and DD took the bus from the resort. Here reply to me when I asked how it went..."It was fine, but I don't want to do it again". I asked why and it wasn't a matter of something going wrong, in fact they had a very short wait for the bus. She just didn't like it.