Well, I actually worked there for several years, both after school in high school and on my breaks from college... As someone has mentioned, the paperbacks are half of the cover price, and hardbacks are usually priced between about 3 and 7 dollars (sometimes a bit higher for recent bestsellers in good condition), significantly less than they sell for new. If you're not choosy about condition, there's also a $1 case and a 25 cent (or 5/$1) case.
Second Looks has a really wide variety of books--many different genres of fiction and nonfiction, children's books, books on tapes, classics, and even a few new books at 20% off of the cover price. The fiction is organized by genre, and within genre by author's last name. The nonfiction is organized by topic, (though not usually sorted by the author's names). What this means is that there's a very clear idea of where whatever you're looking or browsing for is going to be! And if you're not sure of what you're looking for, the staff do their best to be helpful.
So yes. Tl;dr-- Wide selection, books are well-cared for, store's well organized, pleasant atmosphere, prices always struck me as quite reasonable. If you stop by, I'm pretty sure you won't be disappointed