Hardcovers or paperbacks?
Not to sound like a broken record here, but it depends.
Some of it can depend on the length of the book. In some cases, a huge book can be difficult to hold while reading for the first hundred or so pages and the last hundred or so pages if it’s a hardcover. This happened a few years ago while reading Stephen Kings’ 11/22/63. Or the recent entry in the Song of Fire and Ice series. Those were a couple of books I found myself wishing came with a digital copy when you purchased the hardcover.
There are some books that I like to have in hardcover to sit on my shelf.
And I’ve said it before, but I’ll say it again. Hardcover or softcover, I really wish that publishers wouldn’t change the cover design of a series of books mid-way through the run. I like having the spines or covers look similar while sitting on my shelf.
I do like paperbacks for their affordability and the ease with which I can carry them in a backpack or brief case if I’m traveling or taking it to work. But I’m a bit more cautious with my paperbacks (and hardcovers), trying to not break the spine. Part of this is so that if I want to re-read at a later date, the pages won’t all fall out. I picked up a used paperback of the Friends of the Library table for a quarter recently and it’s spine was fairly bent. And as I was looking at it, pondering whether to move it up the TBR list, I noticed that some of the spine was so bent and cracked that the pages in the middle are in danger of coming undone! Grrr!!!!
Nashville Book Worm 
Paperbacks for me. I carry books everywhere, so they’re just easier. And also affordable. And weirdly more comfortable for me to read, just to hold in my hands I mean.