I use ebooks when I need to reduce volume but I really like the use of marginalia in print books. Things that don't get into my lab notes do get into my original sources in the form of marginalia. I mark up my books a lot.
I also like numbering every line of BASIC code. I find it easier to locate bugs and make changes when the lines of code are all numbered.
I can spread out more material on my desk (or lab table or floor) than I can work with on a computer screen. I really feel the difference between the 3-D and 2-D spaces involved. 2-D feels very constricting. (With a computer or two running around the room I suppose I'm occasionally using both spaces.)
Signing with a stylus on touch screen devices is really difficult. The screens are too slippery and held at bad heights and angles. With age my handwriting has gotten shakey. I'm fine when I write large, on a blackboard for example. When I try to write small I am shakey. On a slippery surface it gets worse. I don't mind tapping on tablet PC screens but I don't want to draw or write on them. Could the surface be kept clear but roughened or otherwise made less slick? Would that help? Alternatively one could change the stylus. Writing with something like a sharpened eraser does help some but leaves a residue.