Certainly not a lot of storage - not sure about the graphics card for Lightroom. And of course, quite an expensive machine. Also, one is limited in screen choices to the internal screen, which is very good, but only 27". Also, Apple doesn't sell external 27" displays, so one cannot have a matching second screen.
Yes, the iMac Pro is certainly a nice machine, but quite expensive for what it does and again extremely limiting in hardware choices.
