I have a question about Qimage: Does this print Photoshop files (psd) or do they need to be converted to something else first?
It will do PSD files, as far as I remember. However, I have used Tiffs and Layered Tiffs for the past couple of years, and prefer them. The only thing I know that chokes Qimage is a file with 4 or more channels, which Qimage seems not to understand. On the other hand, I softproof in Photoshop, and include a layer group consisting of the softproof tweaks. What I really like about Qimage is that it will open the file full screen and softproof it, including the tweaked layergroup. When the print emerges from the Z3100 I compare it (under appropriate light) to the softproof on the Qimage screen.
One thing that is essential is to note the paper profile and rendering intent you used in Photoshop for softproofing, and make sure that Qimage is using the same profile and rendering intent.
Qimage Studio also has the best interpolation method of the three versions, although I have been extremely happy with the Hybrid interpolation of the Pro version. Eventually, when the piggybank begins to recover, I will probably upgrade to the Studio version.