gothic.angel
things like "OSX is actually significantly better at handling audio and midi" are old wearisome LEGENDS...
Incorrect.
One exemple - I actually get better performance and latency from my audio interface using Apple's own default Core Audio drivers than with the manufacturer's drivers. Tested and verified time and time again, with my old M-Audio and my current Focusrite interface.
Heck, my old Fast Track can no longer be used with recent version of OSX - unless I wipe AVID/M-Audio's drivers and let OSX take care of handling it...
Another exemple: Apple have allowed for low-latency audio on their phones and tablets
for years. Alternatives are just catching up - see IK Multimedia's recent announcement.
The fact is that Apple has always placed a very strong focus on audio and video - and it's a fact, regardless of whether one likes Apple or not. They're selling systems with audio applications on them such as Garage Band which have to work out of the box. And they do.
They have their own DAW, Logic, which is a top notch audio application, with an all-star line of synths and processors. They have MainStage, which is one of the most widely used host application on stages around the world. And they've just acquired Camel Audio. Clearly, Apple loves multimedia, and they're selling you an experience.
That's where the difference lies - you buy a computer from them, and you're ready to go*. No need to download drivers and install tons of 3rd party tools - everything is integrated. Now, you don't have to like that, and some people prefer custom, and that's alright. But you can't disregard facts.
Last Mac I bought, it took me something like 2 or 3 hours, from the moment I walked in the store to the time I was home, launching my DAW with all its 40GB of content installed. Never had to worry about such things as optimization - unless running Pro Tools which is not the greatest in terms of performance.
* On the other hand, as Mr. Anderton pointed out, the latest incarnations of OSX certainly have lost their simplicity for us audio and video guys. It used to be that you'd pick up a Mac off the shelf, install your DAW software and be good to go.
With Yosemite, and to a lesser extent most OSX revisions since Lion, that's no longer true. If I could buy a few dozen pre-Yosemite computers for the future, I'd do so.
None of this, obviously, takes anything away from Sonar on a PC. It's a different mean to an end, period.