All other things being equal–do you prefer used books? Or new books? (The physical specimen, that is, not the title.) Does your preference differentiate between a standard kind of used book, and a pristine, leather-bound copy? Looking at my library, I have a mix of everything. The most important factor in buying books is price. I don't have a lot of money to spend on my reading habit. So, I tend to buy books from used books stores or publisher overstocks. Most of those books tend to be trade paperbacks. The only factor is portability. I take a book with me everywhere, so it needs to be easy to carry around. (I haven't jumped on the mobile reader band wagon yet, so not dealing with that debate right now) I prefer trade paperbacks for their size (not too big, but not too small) and weight (not noticeably heavy for purse carrying). I guess overall, I am an equal opportunity book buyer.