It's interesting to see the disparity between the comments here and on the post. Nearly everyone below the line on the post is a Linux refugee that's pitched up on a Mac. Here, not so much.
For my part, I have always had a deeply-rooted and entirely irrational hatred of Apple products. OK, the retina screens are nice. Trackpads are usable - but I hate trackpads anyway and always carry a proper mouse around, so no win there. (What happened to those little joystick-type thingies that used to stick out of laptop keyboards, anyway? I liked them.)
But I'm just about old enough to have mostly owned and used desktop PCs. And those desktop PCs have all been custom builds. I'm typing this on a slightly ramshackle Lenovo laptop, which is obviously not a custom build - but I can take the back off it and fool around if I so choose. I've never used particularly outre specialist components or anything; but in some fundamentally irrational way, having, in principle, an absolute say so on what's inside my computer is important to me. Apple's entire business model is antithetical to that. And while I see plenty of satisfied Apple customers among my friends and family, I also see them forking out endless money to Apple support for trivial fixes because of it.
(And I won't be buying Lenovo again, because I do not expect my BIOS to be password protected, and not be provided with the password. :-) )