According to my research;
- Lowes has always had the best customer and contractor's services for big home improvement stores in every area of the country that they have located in their business. That would be Michigan, Iowa, Missouri, Kansas, Arizona, and California. Their staff seems well trained and will tell you if they are not sure and get you someone that is sure and knowledgeable.
- Menards is good but not great for contractors in their opinion. OK for homeowners and DYI folks. prices and products are good.
- Ace hardware has a great staff and many experienced people in most stores. Only has lumbering/ building supplies selected locations but good quality. One of the best Hardware store chains anywhere.