It depends on what the job is as to how many shots I take. I try to take an optimal amount, for PR / Publicity commissions this is less than 30. Studio shots similar. Events can be up to 8 or 900. I have developed a quick way of rating and categorizing images via Bridge that it's not too onerous. An X pro would supplement my professional work, and I doubt I'd take more than a battery's worth in one day, more like 70 or so max.
The other advantage for me is in the weight and bulk. It is like getting back to the Nikon F days with the 105mm f2.5, quality lens and body in a compact package