To Bookswim or not?

Last night I was checking out bookswim, which I think is a fabulous idea and was super psyched to try it out, especially when I saw that they were servicing my area! That never happens. Then I saw the monthly fee ($19.95 for 3 books a month plus $4.99 S&H) and I'm not sure if it's worth it...

Pros for joining

• a lot of books I want to read aren't available at the library and are available here
  
• I buy a lot of books for book groups that I don't really want to hang on to
• I can easily browse for new books
• I can start a queue of interesting books I hear about but aren't quite ready to read
• I'd read more
• I'd read more of the books I want to read through out the year verses waiting until my birthday or Christmas when I get a ton of books I want to read all at once and then only read half
• the monthly incentive would motivate me to finish books for the next swap
  

Cons for joining

• a lot of books are available at the library
• I currently only buy 1 book a month around $10-$15 if that
• it's an increased monthly expense
• I don't get to keep the really good books
  

Really the dilemma is that joining bookswim will not saving me money but will cost me a little more for my reading habit. The plus side is that I would read more (which I want to do) and I could read books that I am really interested in and not just the books that are available at the library. I'm leaning towards yes, but it's just the extra $25. It is a little too high, I was hoping for $15 or $20. What do you think?