That's a tough call! We have stayed at both. POR-Preferred in December 2015 & Boardwalk Villa-studio in November 2017. I really liked both resorts a lot.
The POR-preferred room was fantastic. We used both the South (main) and West bus stops, the walk was the same. We were in building 18, and I had requested a corner room, upper floor. We ended up on a back corner that no one had any reason to walk by. We were far from the stairs, so a longer walk, but it was quiet. The walk to the main building was brief, and the quick service is awesome at POR. We didn't have many table service reservations that trip and we were quite happy to eat at the food court. We ate at Boatwright's the first night, and while I wasn't crazy about my jambalaya, the service was fantastic. I thought the buses were better at POR than at Boardwalk.
At Boardwalk, we requested upper floor near elevators and ended up 5 doors from the elevator (we couldn't hear any noise at all), and on the 5th floor. We could see the fireworks from Illuminations from our balcony. My son really doesn't like the noise from fireworks, so we don't stay in the parks to watch fireworks too often. So being able to view them from the balcony (and in pjs) is a huge bonus for us. We were there over Thanksgiving and had
free dining, so we ate mainly table service. Given that, we didn't mind the lack of quick service options in the boardwalk area, and we took full advantage of being able to pop into the world showcase for dinner.
If you're the type of family that gets park hoppers and likes to eat table service, I might spring Boardwalk. That'll buy you the convenience of walking distance to two parks and tons of table service restaurants nearby. If you're a one-park, barely in the room kind of family, I'd probably go for POR and save the cash. $500 is a lot though - that's quite a few minnie van/uber rides if you need a quick ride to a dining reservation....
Good luck - you can't lose either way.
