$10/month is Ok compared to what? pBooks cost $0/month as medium (paper) is included in the pBook price. pBook doesn't need a warranty, charging, etc.
One of the primary Reader advantages is lower weight and volume per book contents. Once can load many books into a reader compared to much bigger pBooks. However, if it should fail and be thrown away after only 3 years then the advantage is lost. I am not going to waste my time loading a bunch of books onto a gizmo that lasts 3 years, of course. I am not sure I see any purpose for any eBook gizmo that lasts only a few years. pBooks at least can sit on shelf for many decades.