Little late on this, but I will give my 2 cents for possibly the next person with the same question.
I have had DRB for 20 years, and when we were just using TunnelWatch, we rarely called tech support.
Recently we have upgraded to SiteWatch and i now have tech support on speed dial. not necessarily for bugs in the system or down time, though that does occur from time to time, it is nice to be able to call them to make changes to the system now that it is a little more complex. They are also helpful with suggestions. If you gotta pay for it, might as well use it whenever you want