I'm curious if the PP seemed to be as big of improvement as it has to be. I was expecting a subtle improvement, and was shocked to find that the jump in performance seemed to be close to the level of going from no interface to the AP2 - which was close to shocking for me. Then again my laptop and DAC at the time might have contributed to that perception. I was using the Audio-gd NFB-10WM as a dedicated DAC. I have since ordered the Yulong Sabre D18, but haven't received it yet.
I had weird issues with the PP seeming to drop dead, which Philip instructed me how to reset. Since then it has been fine, but it might not have liked being plugged and un-plugged at some point. Just brought out some very nice recordings made by Kostas Metaxas in Melbourne and enjoying the greater sense of space and pinpoint imaging with my whole kit.