I'd pick OKW. I like POR, but the rooms at OKW are bigger, you get two separate sinks (instead of just side by side) and 2 queen beds. The Community Hall and staff at OKW just puts it above POR for me. Everything else is similar in terms of transportation and such to me.
Has Disney recently renovated the studios at OKW? I stayed in late 2013 and my room had a large vanity in the bathroom with only one sink.
Note that there are no elevators at OKW.
Edit: agree with others. Dining options are limited at OKW. No food court - QS is a walk up counter....outside. I'd stay at SSR - you can either walk to Disney Springs or take the boat. SSR also has the largest gym of any of the DVC resorts and a nice spa.