Buying whole beans won't typically save you money on your coffee, but it will improve the flavor. Pre-ground coffee can begin losing its flavor in just 20-30 minutes. Whole coffee beans will last longer than ground coffee, so you'll have a lower risk of throwing out coffee that's gone stale. If you don't mind doing the extra work of grinding the beans yourself, you'll get a better cup of coffee for the money when you start with whole beans.