I am, and it's way better sounding than my iMac directly into the Yggy USB. The latter is a bit bright and strident, as well as sightly anemic in bass. The AP2 w/ Yggy pairing fixes that; it's extremely neutral with a great balance across the board; extremely musical. Some may subjectively find the direct Yggy USB to be slightly more detailed and with better imaging/soundstage, but I think that may largely be an artifact of the brighter tonal balance (e.g. may be mostly perceived detail increase from the enhanced upper frequencies and subdued bass rather than actual resolution), which I can't tolerate anyways.
I'm not fully convinced that the benefits here are due to the AP2/PP itself, versus the coax input on Yggy just being better than USB. I say that because the AP2/PP unit was kind of a tossup when used on the Eximus DP1 and NAD M51 -- and in fact with the M51, the direct USB input was actually warmer and more musical than the AP2/PP, while the AP2/PP was more detailed. The Eximus DP1 didn't change much either way with or without the AP2/PP. But on the Yggy, the differences are much more significant. Unfortunately I haven't tried another coax source on the Yggy to try and parse out where to attribute the improvement.
I was going to sell the AP2/PP before I tried it on the Yggy. And given what people were saying about the Yggy Gen 3 USB at the time (i.e. that it was really good), I was very surprised at my listening results.