I have been using a Sinarback 54H on the Sinar-M for the last 2 months in 1 and 4 shot mode with success. 22 mpx. is more than enough for me and 4 shot is perfect for copying artwork. No problems with the hardware. I am getting used to CS 5.5.1. and patiently wait for the eXposure.
I tried to shoot 16 shots several times and always had some artefacts on the borders of the objects and in the areas of transition of colour in the 100% view in PS. The 50% image looks better. Downsizing helps, I do not output for the prints more than A3. Having the problem I tended to ignore it for a while being satisfied with my 4 shot images. Now I was asked to shoot Russian post stamps and I would like to use the 16 shot mode of the back.
I would like to understand whether I have a hardware problem with my back. I have very limited experience with pixel peeping and for me the images look funny.