Well I got a message from SDRplay yesterday to tell me that my piece of vapourware (I already own a Mk 1 version) will be shipped out to me next week
As for Prog's comments on dynamic range, I am sceptical. I own both an Airspy and an SDRplay and I can honestly see no real difference in dynamic range. Both seem to have around the same ENOB in the ADCs. What I can say is that in my case, the sensitivity of y SDRplay looks slightly better.
I watched the video posted by Leif Asbrink and it was hard to follow everything he was doing, but he appeared to be using a gr-osmosdr driver which had been reverse engineered for the SDRplay and in my experience didn't provide correct control of the device. SDRplay say this driver is nothing to do with them and is not supported by them, so I was dubious as to whether this was really an apples to apples comparison.
When I made my comparison, I used Prog's own SDR# software and I could honestly see no significant performance difference.
I tend to use the SDRplay more than the Airspy because HF support is key for me.
The good news for me was that my second SDRplay is only $149, so even with their proposed Spyverter, Airspy have a long way to go to be competitive with that