We will not make another run of the PCI Catweasel - because maintaining the drivers is way too much effort. And with the current drivers, you wont be able to use it in anything newer than XP (32bit). The next Catweasel will use USB and/or Ethernet instead - but that will still take a while.
I would personally use it on an XP 32bit machine, do you have any old stock left? And why not opensource the driver? the PCI version could be used with a PCI to PCI-express adapter.
Thanks for the quick answer!