In response to the comment on the "just use ABW" from the "another drawback of coated paper" thread:
Earlier last year I was asked to write a few chapters on printing for a digital black and white book, and started making comparisons with different printing methods. The book project fell through, but I had the tests done and made the following blog post a few days ago along with scans of actual prints and density measurements: http://www.bwmastery.com/blog/2015/abw-vs-qtr
I realize that some people see the the straight line curve as a drawback of QTR, but I see it as a huge benefit. By controlling how much more ink goes into the shadows and still having them separate you can have the appearance of dark/rich shadows that smoothly transition into pure black, rather than a noticeable jump like moving up the black point with a levels adjustment. This QTR approch has a similar visual affect to a gamma 2.2 adjustment, but doesn't crunch and compress the last bit of shadows. It does require controlling the tones in the original file and not using a blanket correction curve, but the resulting prints look almost identical to the screen and don't usually require additional ICC profiling or color managed printing. I also realize that you can create ICC profiles to correct for some of the problems with ABW, but if you are going to do that you might as well make your own (or use) QTR profiles and create ICC profiles for them instead.
I am now writing a post about comparing prints made QTR and Epson K3 inks, QTR with Eboni-6 and my QTR profiles, Piezography Carbon K6 prints I made, and Selenium and Warm Neutral K7 prints that Jon Cone made for me last year as comparison prints to use in the book. It might take a few weeks depending on how work projects go though.
Richard Boutwell