Generally, 3 trips a year and we always fly, although in a few years we'll be retired and one of my requirements is to move within driving distance of WDW.
Although you specified Disney, Hilton Head is one of our 3 trips, in a 1 BR. DH and I make another trip to WDW in a 1 BR. The third trip is my solo trip (so WE go 2 times, I go 3) in a studio.