Hi all ! Has anyone had any experience with RME multiface pci interface with Powertracks?

No but if it has current ASIO drivers it should work okay. It would at least work on MME. I looked at those but they seemed kinda expensive, so I went with a Presonus VSL 1818. 8 tracks in, S/PDIF digital, and the ability to add Lightpipe inputs to the total of 18, good solid routing, and a pretty stable drive setup. While i do not have PWTPA i do run it's sister RealBand and it does a pretty good job.