Since you mention self-published books, I'm assuming you're an author. In that case, my answer would be that it depends on your goals as an author. If your goal is to reach as many readers as possible, then Barnes and Noble is probably not the best option, since they cater primarily to traditional publishers. However, if your goal is to build a platform and grow your following, then Barnes and Noble could be a good option, since they have a large brick-and-mortar presence and can help you reach a wider audience.