My plumber told me that he was hesitant to install an insta hot into my house. My current one, that just broke is 16 years. He told me that they were made solid back then. However, the ones today are made much cheaper and are only lasting a year or two. He mentioned a lot of problems with customers due to the decrease in quality. Can you please tell me if they have changed the inside parts since I have last purchased this product-- that is leading my plumber to feel this way?