Did not know they still made paper books????
For my Masters work, I buy Ebook if avail, because highlighting, searching, citing, etc is MUCH easier with E-Book then Paper... but its probably 50-50 on whether or not the ebook exists.
For pleasure reading... if its not an ebook, I dont buy it. I used to have 100's of paper backs... storage and transportation of them was a nightmare. Gave them all away. Now i have a
Dropbox folder with all my ebooks converted to EPub in it. No more transportation or storage issues.
Sure one day tech will move on, but there will be tools like Calbri for converting formats. As long as I keep them in on of the major formats of the day, conversion to new formats should be non-event.