I guess at the time of building this PC, iMac Pro stil wasn't announced.
It would be great to hear what author thinks now about iMac Pro.
It was - but iMac Pro can't be upgraded. You want a new motherboard/CPU for the next gen that comes out in 9 months? Can't just go out and swap the parts out over the weekend. Also the Vega GPU in it is not as performant.