If you think you will be spending the bulk of your time at the MK, then the VWL would probably be your best bet, since you can get back and forth pretty quickly on the little boat, which is also a lot of fun.
However, if you think that you would be spending more time at the hotel and less time at the parks, thewn I would vote for BCV, because their pool complex is amazing!
OKW also looks like it is a fun pool area, with their new sandcastle slide and the children's area is sort of a sandcastle theme.