JOELDI  I have used Bookends for almost two years and now have well over 2,000 references in my database. While I've not used other reference manager programs, I am very impressed with Bookends. It is fast, flexible, and very easy to use. A recent upgrade added the ability to link references so that you know what worked cited another, for example. This allows you to move up and down a "stream" of research very quickly. It's awesome! Updates are frequent, but not too frequent that they are annoying. And... the support is superb! Joel  
(Version 10.4.2)