Running X2 on a Mac

Personally, I would keep the hardware as close to the recommended keystones that are out there. I'd be wary of trying to run Sonar on a system not readily suited for it. With that said, BootCamp can run Windows natively, because it merely scans the system and creates a "driver" disc specifically for YOUR Mac to run Windows, but outside of Bootcamp, I'd only recommend Sonar be used for editing only (if that).
 
I read where another user was attempting to work up a compiled adaptation, but I've not heard Cakewalk working on an OSX version.
 
Even if Cakewalk decided to, I think Mac Pro's are taking away some avenues for hardware developers to use PCI-type cards for interfacing, leaving only the Apple-proprietary and other standard serialized connections. I don't see those as realistically capable of being able to handle large sessions. I don't get that Apple wants to stay in that market much longer, hence one of the speculative reasons MOTU made the shift to support PC's, for example. Again, speculation.