The simple is basic fact is, go where you like it.
Someone with a carbed hemi comes to me, im not going to be much help, but a fuel injected OHC, and im a bit more knowledgable. Im not saying i dont know a bunch about it all, just older motors i get sketchy on the specifics.
I absolutely hate napa, every time ive gone there even before i worked at advance they've been no help, cant manage their own books and computers, cant find the parts, and the customer service has been shitty. But someone else may go in and get great service from an employee that wasnt there when i was, and become a NAPA customer for life.
My suggestion is find the service you like and stick with it, sometimes for hard to find parts you'll have to go somewhere else, but as long as you have someone that is trying to help you, you will enjoy it.
-Jono