Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Working well, no problems

Hasn't stopped, hasn't stuttered. Be aware they want to you take it apart and clean it every week, and the motor every other week. It won't go forever if you don't do maintenance - weekly, not seasonally. Considering I had a couple of smaller ones (different company) for a cat, that stopped within months, this makes sense to me.So far, the only 'difficulty" is that the cat tries to wash in it. It's that big.