Last year shoppers spent $405 billion at Wal-Mart, the world’s largest retailer. But according to a new study by the Consumer Reports National Research Center, they might be better off if they switch stores.

For all the talk about Wal-Mart’s low prices, 30,666 subscribers CR surveyed said the prices at 10 other retailers, including JCPenney, Sears, Dillard’s and Meijer, a Midwestern chain of superstores, were at least as good. And bigger wasn’t necessarily better when it came to the overall shopping experience. Almost three-quarters of respondents who shopped at Wal-Mart found at least one problem to complain about, and half had two or more complaints about the store or its staff.

Wal-Mart was the sole chain to receive below-average quality scores in more than half of the product categories. Only about 10 percent of Wal-Mart shoppers thought the store’s children’s clothing was excellent, for example. By contrast, 46 percent of Dillard’s shoppers thought the kids’ apparel was top-notch.

Wal-Mart and Kmart scored notably lower than the other chains, but Costco stood tall. In addition to citing the warehouse club’s rock-bottom prices, survey respondents praised its bang for the buck: It was the only store judged much better than average for value. In CR’s surveys over the years, Costco has earned high marks as a source of a surprisingly large selection of goods, including mattresses, groceries and books. In recent years, the chain’s Kirkland Signature products have often performed well in CR’s tests.

Other findings

• Four chains earned outstanding scores for merchandise quality: Costco (watches and jewelry, personal-care items, hardware, home decor, kitchenware, electronic entertainment such as music and DVDs, and sporting goods and toys), Dillard’s (men’s, women’s, and children’s clothing; personal-care items; home decor; and kitchenware), Macy’s (home decor and personal-care items), and Sears (hardware).

• Target’s “cheap chic” goods didn’t wow everyone. Despite its high-profile partnerships with fashionistas Cynthia Vincent, Eugenia Kim and Zac Posen, survey respondents judged the quality of Target’s women’s clothing and watches and jewelry below average, and the store’s kitchenware, home decor, and men’s and children’s apparel average.

• In addition to a lack of sales help, the most prevalent problems were that desired items were out of stock and that checkouts were jammed. In fact, 29 percent of shoppers CR surveyed complained about long lines. The problems were much worse than average at Kmart, Wal-Mart, and Meijer.

More service gripes

• Slow checkouts. Twenty-nine percent of shoppers complained about a lack of open checkouts or about lines creating bottlenecks. Lines were worst at Wal-Mart (cited by 46 percent of readers who had shopped there), but they were almost as bad at Costco, Sam’s Club and Meijer.

• Shoddy service. Relatively few shoppers sought help, but 24 percent of those who did speak with a clerk said they had a tough time finding one, and 15 percent of those who spoke with a clerk said that the employee wasn’t well-informed. Wal-Mart and Kmart had the least knowledgeable staffers, according to readers.

• Empty shelves. Readers who shopped at Meijer complained the most about out-of-stock merchandise: 25 percent of respondents said the chain lacked an item they wanted. Wal-Mart, Kmart, and Target also had trouble keeping regular merchandise in stock.

• Difficult layout. Thirteen percent of shoppers complained about cluttered displays or narrow aisles, but a disproportionate percentage of Wal-Mart and Kohl’s shoppers said that those problems hampered movement.

• Hidden price tags. At most chains, price tags were in plain sight, but at least 12 percent of respondents complained about missing or hard-to-find tags at Kmart, Wal-Mart and Meijer.

• Lengthy returns. Few respondents had trouble returning or exchanging merchandise. The biggest difference among stores was how long it took to complete the process. Wal-Mart shoppers were particularly peeved; 20 percent of the returns took more time than expected.Last year shoppers spent $405 billion at Wal-Mart, the world’s largest retailer. But according to a new study by the Consumer Reports National Research Center, they might be better off if they switch stores.