I'm also using 2.2.0. The reason I asked is because the newer PWDs can't be loaded with software version 2.0.3, which is supposedly preferred by many. According to the PS Audio forums, an updated digital input board is to blame, as only 2.2.0 has the drivers for it. I know Paul himself prefers 2.2.0, but I'd like to be able to decide for myself... Oh well.
Regarding the bridge firmware, the latest version sounds congested to me (2.14b). I've stuck with 2.13c since I received my unit. The only downside is the pause function does not work correctly with this version and will skip to the next track instead of pausing the current one.