I had both USB cards in the system for a while to compare.
Pink Faun on the left, JCAT on the right. Both were powered externally by the JCAT OPTIMO 3 DUO with 5V power.
Pink Faun makes a lot of impression. Here is the picture with the "middle" OXCO clock attached.
Some electrolytic capacitors can be seen and there is only one USB port.
Here is JCAT with the Emerald Oxco Clock.
The heat sink is pretty powerful.
In comparison, Pink Faun turned out to be demanding. Many services are switched off in my optimized Windows 10 Pro system. Pink Faun didn't like that. JCAT, on the other hand, ran immediately without having to reactivate services.
In terms of sound, Pink Faun had a fuller basic tone for me, while JCAT resolved very detailed and offered very good transients. I didn't feel the differences very much, however. Both cards play at a very high level.
In my system I preferred JCAT. This card seems more modern and I also liked the quality of workmanship best. The difference to the predecessor JCAT Femto is extreme. JCAT USB XE plays a lot better!