Biggest current downside of purchasing at BWV: its end date is 2042 whereas AKV is 2057, BLT is 2060 and SSR is 2054, and OKW when buying from Disney is 2057. May not mean much if you are older but can mean a lot if you are a young family. Also note that BWV is less expensive to buy in the resale market than from Disney.
Pros: ideally located with easy access to Epcot and Studios (you can walk to both or take boat). You are essentially within walking distance of over 20 restaurants -- at the Epcot resorts, Studios and Epcot. If you get boardwalk view rooms (a guaranteed booking category), you will have one of the best views in WDW looking over the lake at the other Epcot resorts, seeing Spaceship Earth in Epcot, and can watch from your room upper level fireworks at both Epcot and MK. Has lower point standard view which is not a bad view and points are really not much more than low point resort OKW. (For either boardwalk view or standard view you should plan on usually booking 11 months out bercause those rooms can often fill early in the booking process.) Nightly entertainment is decent, restaurants at BWV are good and sports fans have the ESPN club. Main pool is right on the BWV side and is a good pool with a long slide and a good bar. Quiet pools are also nice, one on BWI side is in very quiet area and hardly anyone is ever there. Good community hall. Rooms are decent size (smaller than OKW but about the same size as SSR, BCV and VWL). Rooms were just recently redone so right now rooms look almost new.
Cons: if you have a car, parking can be a pain sometimes because far too many get away with (by lying) parking there and then going to Epcot or Studios. Bus sytem to MK, AKV and Downtown Disney is one of, if not the, worst on site. It shares with Swan/Dolphin and sometimes with YC/BC and thus trips can often be very long. Also, for no explainable reason, you can, more than with any other resort, find yourself waiting more than 40 minutes for bus back from MK to the resort (and that is not just during rush at closing). (That has happened to us at least once on every trip we have taken there; we stand there and watch as busses come for every other resort at least twice while waiting for a BWV bus). If room is at end of hallways you can have a somewhat long walk from elevator/lobby to room (however, one at AKV Kidani is three times as long).