Hi,
Yes, I'm using Q-Checker when I'm finishing something (CATPart, CATProduct, Model or Drawings in v4 or v5).
You can run it also from VPM directly.
Basically, its corecting some small errors done during your work (things which might be corect for other companies but not for those which gives you a specific profile).
The software allow you to corect automatically some mistakes but for others you have to repair it manually.
You can see also the area where the problem is existing and the element which create the problem.
The best way to understand the software is to read those manuals for your version.I know there are a lot of pages but...
Regards
Fernando