Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Bosch does not provide a lasting product

I had a Bosch Powerstream tankless electric water heater installed when I built our home 5 yrs ago. The heater never did work properly as it would always change temps while using the water. Only for about one minute but long enough to notice while in a shower. Finally, it gave out after five yrs and I called the 800-798-8161 line for assistance. The person I spoke with was very difficult to understand as he was foreign. He also had a terrible attitude and acted as if he was doing me a favor by speaking to me. He was unable to solve the problem and was not able to advise how to proceed. So I threw out the Bosch and bought a hot waster heater at a much lower price than Bosch's tankless ones. I will never by a product of theirs again.