I have 3 coffee grinders, a hand cranked burr grinder, and 2x spice grinder type ones. One from Lidls for £6.99 and one from Asda for £10.99. Oddly the Lidl one isn't too bad, makes very drinkeable coffee. The asda one though being the same size, makes the same beans taste horrible. While not quite burnt, there is a distinct under extraction going on, the coffee is bland and one notey. Not quite sure why this is, I should check if the blades are the same size/sharpness.