Two bowls are useful so that you can use one for cumin and the other for when you don't want the spice you are grinding to taste of cumin.

Each bowl has it's own set of blades, which is excellent, because you can just pop another bowl on, opposed to having to switch the blade from bowl to bowl

so I could change the bowl to grind spices.

I love the three different bowls for grinding

To clean the bowl after resins use alcohol and sos brillo pad to get any stickiness out of the unit.

The coffee one is the perfect size for grinding whole beans for a full pot of coffee and the fact that I can remove the bowl to dump the grounds into the filter is almost the best part

The multiple bowls are very convenient.

This grinder has a couple stainless steel grinding bowls that will never break down.

These stainless steel bowls are

The three bowls makes it easy to move from one herb to the next without having to wash out a bowl and then wait a day for it to be completely dry

I also like that the bowls can be taken off the machine and cleaned, something you can't do with most other grinders

I only use the bigger bowl to grind coffee

I like the removable bowls

The set also comes with plastic lids to top the 1/2 height bowls so you don't get power all over the place when grinding, and also a perforated shaker top (like that of a salt shaker)

Works great the extra bowls are very handy, I'm using this in a professional kitchen and it gets used a lot.

I was very excited to find a grinder that can do coffee separately from spices and is easy to clean--just put the detachable bowls in the dishwasher.