I'm running on a Mac Pro using boot amp under Windows 7 Pro... I've had no problems at all related to the running of Sonar or any other windows program... Running for over a year now... I only have Lion installed on the OSX side as I've had no reason or need to chance changing anything...
Tho I work with it when I must, I have no personal need or desire for OSX so the Mac is set to boot into Windows by default. It simply runs as a high power dual Xeon Quad Core machine with 16GB of RAM... I couldn't be more pleased with the hardware.. (Well, the machine has support for 3 monitors if I could only afford to buy one or two more ;-))...
Why bother to spend the time/energy to make and support another version...
If you want need to stay in OSX but still have access to Sonar, I'm told the Parrallels software does so very well...
I'd much rather the Bakers stay focused on developing for a single platform... There are enough problems with that... I'm sure you notice that many of the soft wares supporting both platforms work well on one and not so well on the other....
Keni