Pass Labs X-1 -vs- Ayre K-1X Preamps

Has anyone owned, heard, or compared the Pass Labs X-1 and the Ayre Acoustics K-1x preamps head-to-head?
If so, what are their sonic strengths and weaknesses in comparison to one another?
Thanks in advance.
I shopped at AudioConsultants. They sell both brands. The Ayre was my choice by far. This wont help you much as if I had a different system, mabe the Pass would have been better?? But in my system, the only similar performance was in the quietness of both. Musically, the Ayre was much more fun to listen to. I believe that I can't speak for Pass then but I will say that the Ayre in my oppinion is better than the super amps being touted in the mags by a long shot! That includes Bat,VTL and tubed units like Hovland etc. I say this because the preamps I mention, all have a house sound-put them in the system and I could pick them out blind folded no problem. But the musicallity of the preamps differ dramaticly. Dynamics is top priority for the jump factor needed for lively music. The Ayre just does it much better than any other pre I have head including the big CJ. No tube bloom though-just keep that in mind. I use tube amps though. I do want to put a good word in for SupraTek on the tube side.
I have listened to both too. Ayre K-1x has my vote. It is really neutral and fast. Of course it also depends on your accompanying equipment for synergy. I would at least get the V1x also if I am going the Ayre path. Have a listen to the Spectral 30SL too. It is also a great product!