We just stayed at BCV. Lovely resort (fantastic pool, restaurants, etc), but I HATED the transportation, especially with a little one! The busses were very inefficient and took FOREVER. The walk to Epcot was nice and really close. However, the walk to DHS is really, really long and hot. We got turned away from the boats twice due to them being filled to capacity and we decided to walk instead of wait for the next one. I just find the boats to be a nice optioin, but incredibly slow! We found the BCV to have the worst transportation of any of the resorts we have stayed at.
I haven't stayed at the AK since the villas opened, but I agree with the others that it has GREAT bus tranportation. Probably the best we have experienced at any resort. It is really close to AK and DHS and not a far drive to Epcot. The trip to MK is longer, but all highway so not bad either.