Instruct: Classify a given Amazon review into positive or negative sentiment.
Query: Great Toothbrush but....

First of all, I agree with all the other reviewers that this is a fantastic toothbrush that will keep fillings away. In fact, it's so fantastic I have bought a total of 4 for myself and my family. However, if you are one of those people who apply ANY pressure on your teeth with the brush while it's working, be warned that the life of this unit is very very limited---the head of EVERY single one of our brushes broke off within 3 months of use!!! The company was remarkably unhelpful and unsympathetic! We now use the Oral B brush, which is almost as good and at least last long enough to go between dental appoointments.