I work professionally with photo and video and have been thinking of getting the x3 myself as well.
At work i have the surface pro 4 with the m3-6y30 and 4 gigs of ram. It can actually handle the raw files from a 5D III quite good. draggings sliders and doing color adjustments is actually pretty fast. no real time but very managable. Its more distortion type effects that will require more patience. I actually think the x3 would perform better than my surface because of the 8 gigs of ram it has and because the surface has a much higher resolution which drains a lot of power when rendering
Combine it with a wifi sd card and set it to transfer the raw files as you shoot and you have a very descent way of checking your results awhile you are out and then finalising the shots back at the office on your workstation