I received the first insert and there was a problem with the heater kicking off. I called and reported it and was sent a new part, replaced it, and still had a problem. I was sent a new insert immediately and it works wonderful. I love the product and would definitely recommend it. I have since bought two more for my children who feel the same. We are all very pleased. I wish all companies were so easy and efficient to deal with. Wonderful product, wonderful company. Thank you.