Ace hardware is one of those staples in a small town community... They aren't flashy, they are a little expensive but and they don't have everything that a large box store would have.
My review would be 5 for customer service (and the post office) and 3 for he rest of he store.
I can get most everything I need in one store and for a better price by going the same distance in the opposite direction. But I won't ever get the same small town greeting that I seem to always get when I come to Ace. And there is always someone there to assist you with a huge smile on their face.
This location, in particular, also has the most under-the-radar post office. Need to skip the long lines at the Davidson or Cornelius post office? Head to the back of Ace hardware in Cornelius to send your items. I honestly don't know if they have ever single service that a stand alone PO has but I have yet to have any issues here. I mostly send things that may or may not require more than one stamp so I head in for their expertise.