I was a member at one point. At the time I bought books all the time so it was kind of cool. You save a decent amount on hardbacks I believe. I don't remember all the benefits I just remember that I went in there thing I would spend a certain amount and would come out spending a bit less.
I would suggest you look into it. I found some links that might be good to do so.
Also, if those don't answer your question try googling reviews of what other review members have to say. It might help.
Best of luck,
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