I mentioned the metal impeller, because that's one of the features that makes it easy to select the "good" model. The one with the metal impeller is overall better than the very similar model with the plastic impeller. The price is close enough, and the packaging is close enough that's it's easy to go home with the inferior model. I think one is called "super" and one is called "Ultimate". When I bought mine, I had researched it online. At the store, there were a lot of the plastic impeller model on the display, and since it was about the right price, I was almost fooled. In looking for a carton with less damage, I found ONE of the metal impeller models behind all the plastic ones, for $8 more.