YES. This is what I use the GXR for. And works so much better than my Epson V600.
I use it both for 35mm and 120 copies. I'll take a photo of the setup tomorrow but here's a list of the bits I use.
GXR
-Leica bellows
-Schneider Componon-s 50mm for 35mm film copies (+ltm adapter)
-Rodenstock Rodagon 80mm for 120 6x6 and less copies (+ltm adapter)
-Lightbox
-Film holder - either mounted stides, epson film holder, or the film holder from my enlarger, which is the best method for film flatness
-Copystand or enlarger or tripod to mount bellow and camera
I'd recommend using an enlarger lens as they are design for copying purposes. They outperforms any other lenses I have tried for this purpose. The fine adjustment on the bellows helps to get accurate and sharp focus.
Coping 35mm with the whole sensor (3:2), I get a good image size with minimum files size (compared to the massive ones when scanning with the V600). With medium format the image size is less due to using the 1:1 aspect, but for quality they beat the V600 and though the image size could be bigger, it's fine for images destined for the web, or viewing on screen, or as a preview to wet printing, which I do.
I'll post a few pis tomorrow.
Mark