I was going to say the same thing on number of teeth, but also how they engage. When you look to see how the teeth engage, some brands stagger the engage, meaning all the teeth on drum tooth line, don't engage at the same time. This allows for more power per tooth. My Diamond mulcher allows for using different teeth styles on the same drum, and reversing the teeth as well (depending on which tooth your using). There are a lot of things to consider on a mulcher to make sure your getting what you need. FAE is a really good mulcher in my opinion.