One does indeed get sludge using a blade grinder, but it's not nearly as unpleasant an experience if the coffee is good. That said, Kitchenaid makes a great burr grinder for drip or press use. Low-end burr grinders are also pretty cheap. There are of course many very expensive espresso grinders, but they are best at making an espresso grind (very fine) and may not be good at medium or coarse settings, or may not have them at all.