No argument that the current eGPU setups are a hack, that doesn't change the facts about USB graphics adapters - they're hacks.
There's a few simple things to take as read:
- The iMac has an unacceptably reflective screen.
- The MBP with discreet graphics will probably die from thermal fatigue running that many screens, if history is any guide.
- In Australia at least, the nMP is, in real terms after currency equivalence, $1000 more expensive (plus sales taxes) than the US prices.
So we have a choice of machines that are unusable in a lit environment, destined to burn out, or grotesquely overpriced.
Back to square one - eGPU or Hackintosh. Personally, I'd prefer to invest more than the cost of an iMac in a reliable Mini/eGPU setup.