When getting a prescription filled, you don't want to have to wait a long time or, worse, be told the medicine is not in stock.
A Consumer Reports National Research Center Survey found some stores deliver much better service than others.
Walmart was at the bottom of ratings. Readers complained of a lack of personal service and long waits."
The big drugstore chains like Walgreens and CVS didn't fare much better.
"Fifteen percent of those who shopped at chain stores complained that within the past year, their prescriptions weren't always ready when they were promised," Kim Kleman said.
Far better was service at independent pharmacies, as well as two independently owned franchises - Health Mart and The Medicine Shoppe.
Customers cited faster service and said the independents were much more likely to have medications ready for pickup when promised. But a Consumer Reports' price check found that independents can cost you more.
"If you're taking a generic drug, you can save money at big retailers and chains. For generics, they charge as little as $10 for a three-month supply," Kleman said.
For brand-name drugs, Consumer Reports found the cheapest prices at reputable online retailers such as healthwarehouse.com and familymeds.com.
For example, Nexium cost $172 for a month's supply at Healthwarehouse compared with $230 at CVS.
Consumer Reports says many supermarket pharmacies did almost as well in customer satisfaction as independents. Many supermarket pharmacies have frequent-shopper discounts and provide health screenings, vaccinations, and free antibiotics.