Ditto on the comments about the Canon iPF printers. They do implement 16-bit printing well. However, in my experience, it's mostly seen when you have a very long, subtle tonal graduation (large expanse of sky) and especially for B&W. Otherwise, I find there are times the 8-bit driver is just as effective. I know this doesn't help you much with your Epson dilemma, but I don't think Epson has truly implemented 16-bit printing the way Canon has. Therefore, I don't think you'll see a lot of difference.
As for the Mac vs. PC debate, don't let yourself be complacent. Mac Malware is out there and expanding. Up to now, PCs were the target because there are so many of them in use -- bigger bang for the buck. But with more Macs being sold, it's a larger target audience (ditto for iOS). Here's an interesting blog from ZDNET: New MAC OS X scareware
Personally, I use PCs. A lot more bang for the buck. My wife, with 25-yrs as a graphic designer, has used Macs for years and is having a tough time ponying up $3500 for a new computer that I could buy/build as a PC for her for about 1/2 the cost. And honestly, once you work in InDesign, Photoshop, etc., there's basically no difference. And let's face it, how much time do you REALLY spend with an operating system (yes, it's the underpinnings). However, since we share an office, I know my wife has at least 2 or 3 program crashes or system lockups A DAY. A lot more than I have with Win 7 x64.