I haven't written about Booksfree before, though the owner has commented in a couple of threads about Bookswim. Booksfree seems to be essentially the same service, except Booksfree was here first and for several years. Since they are actually in business the subscription plans are available to see and compare to Bookswim...except that Bookswim's rates are not posted yet.
The plan rates make sense, are comparable to Netflix's plan, and I think it works.
I still don't think that a book rental plan makes good sense for me since I have such a strong local library system in my area, but without having tested the plan it looks like Booksfree has the right idea...but as always, only for those who don't have access to a good library system.