- It's all about making it easy for yourself. In short, motherboard and GPU choice change the experience from 'almost effortless' to 'never gonna work'. Get a $20 USB external soundcard to get rid of any audio configuration quagmires. Get the most compatible, widely used motherboard and Nvidia GPU, so you can get support on Tonymac should you need it. Stick to wired Ethernet to avoid meddling with bluetooth and wi-fi if you can. Everything else (PSU, CPU, RAM, hard drives and case) isn't an issue.
- The tradeoff is time invested into initially understanding how it all fits vs. money saved and increased knowledge of how MacOS ticks (a good thing regardless, if you're a power user). How much time depends on how much of a PC tinkerer you are already. If you already built PCs and tried getting Linux distros going it's gonna be second nature.
- You'll still need to check out Tonymac when a point update comes out for tips and warnings. The easiest solution is to install the fully up to date next-to-last MacOS version (install El Capitan 10.11.6 now that we are in the Sierra cycle, for example) and keep it going until you're forced to upgrade. Staying a generation behind, both in hardware and software, is the safest strategy. Hackintosh and being on the bleeding edge don't really mix.
I would agree with the overall sentiment though and add that even on a legitimate Mac it's usually a good idea to hold back a bit on updating. I work with audio a lot and it's common for audio units (and Pro Tools if you use that) to break initially.
Also, some of the original setup requires a bit of tinkering with drivers to start with (especially if you use 'recent' hardware) but it's really not more complicated than installing linux these days (and then fiddle a bit with the settings).
To get solid bluetooth support I bought a card from http://www.osxwifi.com/ , which makes peripherals like the magic trackpad work smoothly.
Odd kernel panics used to happen once every 3 months. Black text would scroll down the screen and you have to hard reset the system.
I would keep a legit backup around but the power/price ratio cannot be beat. I'm looking at building another soon.