Both of these DACs are reviewed at WHF. While the airDAC received 4 stars (due to losing "layers of subtlety and detail," and lacking a USB input -- among other things), the irDAC received product of the year award at its GBP 400 price range. That, in and of itself, should tell you something, if not a lot. As for the airDAC's wireless capability, I know AirPlay is restricted to playing Apple's lossless files -- if memory serves me right -- up to 16 bit - 48KHz. So that is one draw back, which, by the way, can be circumvented by using a different UPnP streamer. Also, the airDAC uses the b/g/n technology, which is prone to a lot of interference (and that should impact the quality of audio delivery too). On top of all these, I think the airDAC's supported sample rates goes only as high as 24 bit / 96KHz, while irDAC's go as high as 192KHz. I, personally, own an irDAC; and I love it. it is as every bit good as the people that have reviewed it on WHF say it is. Unless, you want to spend a lot of money on a really refined DAC, this is one of the best options at its price point.