"Napa - usually best counterman; good/great quality parts; 70% wholesale"

That does conform to my impression over the last 30 years.. including the description of O'Reilly's....

but it is a 6 mile round trip to O'R's...and 60 to my nearest Napa...

The differences in training and knowledge really showed up back in the days of paper catalogs in a 10 foot line... they had to know WHICH catalog to check in ... Sometimes the computer keeps them from finding the obsure stuff... which is usually what I am dealing with...