I have read this thread and was surprised to find no mention of one of Qimages most impressive and useful features and that is it's ability to queue many images on many pages as well as fit images of different sizes together in a way that saves paper and minimises cutting.
When I tried to use this feature, Qimage didn't show nor took into account the printer margins (3-4mm on every side with my R1800). The result, when I wanted to print 2 A5 on a A4 sheet, was that the margins were uneven around the images once cut in the middle of the paper.
At least as far as I know about Qimage (not that far I confess), LR behaves much better on this particular problem : set margins to Xmm, cell spacing to 2Xmm, and everything is centered on the paper.
With Qimage, when I try to do that, the images are centered on the display, but adding the printer borders, it's off - I'd need to have a greater border between the prints, and didn't find how to do that automatically.