Majority of espresso drinkers prefer flat burrs because you get to taste more flavour and depth in your coffee as compared to conical burrs. Well, the debate goes on, and to each their own. By solely looking at the trend in commercial cafes and influential grinders in the market (Mahlkonig EK43, Mazzer ZM & Lagom P64), statistics do seem to indicate a consumer preference for flat burrs. Except Standard Flat Burr (made of Steel), there're Titanium Burr & DLC Burr fitting DF64 Grinders. 64mm Flat Burrs Titanium Coating Thickness: 2.2un Friction Coefficient: 0.4 Features: High surface hardness and improved wear resistance Disadvantages: When aligning the burr, due to the high friction coefficient, the coating is easy to peel off when alignment of the burrs. In addition, the ground coffee powder is easy to stick to the surface of burr due to static electricity. DLC - Diamond-like Carbon Coating Thickness: 2.0un Friction Coefficient: 0.15 Features: Very low surface friction coefficient, self-lubricating friction amplitude be formed on the surface, with diamond structure and high hardness. Advantages: The adhesion of the coating is better. During the alignment of the burrs, the friction coefficient is small, the coating is not easy to peel off after the burrs are scratched. In addition, the coating is a non-metallic element, which can effectively reduce the electrostatic effect. The coffee powder is not easy to stick to the burr surface and is easier to clean.