Paper for me. I grew up with a paperback book of some type nearly always at the ready for a quick read and now, many years later, I prefer the experience of paper over digital.
Sure, it is likely partly sentimental over practicality, I admit it, still the part of the enjoyment of reading a book for me comes from the physical tactile response of slowly turning a page of a horror novel or quickly turning them while reading a good sci-fi story. The smell of the pages from the humidity of reading a book from the protection of a covered porch during a rain storm. With paperbacks the spine & covers tend to get wrinkled over time and on subsequent reads you feel the ridges with your finger types.
With so much else of my life taken over by digital, books are one of the few analog parts left that I will likely never switch away from.