has anyone tried PS Audio perfect wave duo

I think very few people have heard them, just beta testers. Their impressions on PS Audio's forum have been generally quite positive, with three caveats. First, the Transport/DAC supposedly sounds best on high-res formats that are not widely available commercially. Second, the units supposedly sound best plugged directly into an amp rather than a preamp, which creates a problem if you listen to vinyl. Third, the products may not be completely bug-free at this point and some of the functionality (like wireless music server capabilities) has yet to be developed and is not scheduled to be released until the end of the year.

I own the PW DAC and Transport and would agree with general impressions. The combination of the DAC and Transport connected via HDMI/I2S creates an amazing synergy that makes for a fantastic source. This is the best redbook playback I have ever heard, hands down. But...I would not rush out to buy the PW DAC as a standalone unit because other digital sources plugged in via SPDIF and AES inputs sound pretty good but not amazing. If future products that are in the works at PS Audio bring the sound quality of other sources plugged into the DAC up to the level of the DAC/Transport combo, then it will be a phenomenal system that offers the flexibility of a wide range of digital sources with wonderful sound quality.