The K-cups don't work properly. It starts out seemingly okay, but at the end of the brewing cycle (when the spurting begins), the foil top of the K-cup separates and dry grounds fly out of the Keurig machine. This isn't a fluke; it happens every time. So the workaround is to open the K-cup, dump it into a carafe, add hot water, stir, and wait 5 minutes. Then pour it through a standard paper coffee filter and enjoy. A bit of a hassle, and I'm surprised that VitaCup didn't adequately test the K-cup. I'll never buy it in the K-cup again, and you shouldn't either unless you like vacuuming up grounds or doing it manually. Cheers.