New Owner of Sonar and MC5 - how do I know what is an update for me?

Dear all
I purchased Sonar 8 in April 2010. I then purchased MC5 just a couple of weeks ago (long story!). What I would like to know is these posts that indicate updates for instruments etc, seem to be quite old. As I have purchased MC5 and Sonar 8 just a couple of months back, do I have these updates already, or should I still download them?
Thanks very much for your help
Jim