Mazzer sell the Robur because it heats up more slowly when grinding large volumes of coffee.
So to conclude, I think anyone who buys a Robur for home use has more money than sense. I have a Mazzer Mini at home. What can I criticise? The taste? No! If I wanted to be super critical I'd say it takes too long to fill the portafilter, and that is the only reason I could think of for moving to a larger grinder.
Off-Topic:
Off-Topic: