Ask HN: Is this where I use a CMS?

I am building a website that contains simple content (but not a blog). The only non-text/non-image content is a few ajax calls to run some calculations on the server and outputs the result for the user to see (I am using clojure and compojure for this).

However, some of the pages in the site are considered "premium" content and require paying via paypal/google checkout/etc before having access.

I have always been a "roll my own" kind and never paid much attention to the CMS's out there to know what their limitations are. But since the only functionality I have is user restrictions on pages (which may require some API calls for payment processing) and the occasional ajax call to compojure, is this a case when using a CMS like wordpress makes sense?

Note that the content is relatively static, but shares a lot of styling across a decent number of pages. I care more about customizing the look/feel of all the pages easily more so than the ability to create new content pages easily.