Hi Per,
I haven't tried PDF-XChange when printing from Qimage-U yet, but it shows as a printer in the Qimage-U printer Printer/Page setup dialogue.
Yes, it works ok but PDF-Xchange Lite does not have any colour management features. It's probably ok if you use sRGB images but colours are a little washed out if you use Adobe RGB, or in my case raw images with a camera profile. This is with Qimage set to "let printer driver manage colour".
Printing images to pdf works better with PDF Creator because it does have some colour management ability; I found that in PDF Creator, setting "printer manage colour" or "host system manage colour" both worked quite well and resulted in pdf images looking about right on screen.
Link to PDF Creator:
http://sourceforge.net/projects/pdfcreator/PS. I just tried PDF XChange Lite again and set QU with a printer profile of sRGB and got good results.
Terry