If you're all about mating faces to each other then this isn't the topic for you.  The more experienced I get in using SolidWorks, the more obsessed I've become to utilize default-workplanes/origin (DWP/O) as much as humanly possible.  This means that when I insert a component/subassembly into my assembly, I may use faces in making it concentric, but I will use the subassembly's (not the selected component's)