Hi,
Never really had a MAC, but I've fiddled with a few of them, and used to do Internet Support for them ... but that was 10 years ago and before.
All in all, the only complaint I have about MAC's, is that most of them are not easily upgrade'able and in essence they are a part of the throwaway society. You are paying a premium price and it won't last half as long as the PC's.
I still have the P2's and P3's with XP-Pro on them, and they run great ... and two of those are now over 10 years. The other is 5 years with W7-Pro on it now, and another one 3 years old with W8-Pro on it. And I have upgraded the memory on all of those (XP's have 4 and the others 8) and I can upgrade the Processor in the two newer machines if I want, though the other 2 will probably live a bit longer. One of them still has an old AGP motherboard! ... I'm looking to switch motherboards/processor and such on that one sometime this summer. That computer happens to have my M-Audio 1010L card, and is the one that the Midi Keyboard and all the VST's are on.
I like the flexibility ... my W7-Pro machine will get the Audio Card when I upgrade that machine and swap places, and the new machine will become my biggest and best.