I've contacted printed a fair amount of 4x5, and while not optimal, for certain subjects it works pretty well. Strong graphics in cyanotype, nicely matted, can be quite striking and intimate; kind of like peering through a keyhole.

Still, with ~ 20 sq inches of film, it seems a shame not to at least enalrge to 11x14, a size which separates the Svens from the Goats if you're packing a camera big enough to make negs for contact prints.