As Bruno said, the iMac is currently very out of date. Odds are, the processor is not the latest generation. RAM and SSD prices are out of date (and of course carry the usual OEM markup).

If your timeframe allows, I'd say wait. Apple is due to refresh the iMac any day now, likely sometime this month. Should being the SSD and RAM price down, along with newer CPU options to properly match the other vendors.

Hackintosh? I personally wouldn't. My experience with them in the past has always been a little wonky. It's fun to hack around with if it interests you, but I'd never depend on one. The low level driver hackery can and does lead to instability.