Instruct: Classify Amazon reviews into positive or negative sentiment
Query: not a great mixer. barely does what it says and not for long.

You have to press the cup down coninuously to ensure proper engagment of the coupler to the blade. if you don't press correctly ordisengage evenly, little pieces of plastic get stripped off. very soon, the coupler no longer works at all.Its a poorly designed system. I do not recommend it.