The biggest difference between Great Value K-cups and most other K-cups is price. Great Value is Walmart's store brand, and the price of Great Value K-cups is significantly lower than most other brands. Because Great Value is a bargain brand, Walmart produces the Great Value K-cups in huge quantities, so the taste and quality are not identical to name brands and some consumers don't like the product for that reason.
Like most other brands of K-cups, the Great Value K-cups work with Keurig or Keurig-like machines that make single cups of coffee by placing one cup into the machine. Great Value K-cups come in a variety of popular flavors and strengths, and they work with most standard brewing machines, though they are specifically manufactured for Keurig machines.
Great Value K-cups have a different taste than other brands on the market, like Dunkin' Donuts and Starbucks, though they contain the same type of coffee beans as other K-cups. Walmart designs this product to replicate more expensive versions but makes such mass quantities that they sell the brand at lower prices. Some consumers do not like the taste or feel that the K-cups do not come close enough to their preferred brand, but generally speaking, aside from price, the products are relatively the same.