As a digital artist, It is fine to support your favorite artists by having some of their wallpapers up. I use one of Justin Maller's Facets as my wallpaper even though I could easily create something very similar. It's kind-of like wearing a jersey with your team's colours.
Since you are a digital artist, do you use a graphic tablet for drawing? I am not much of a digital artist.. I find it kind of hard to draw on a computer as opposed to drawing on real paper.