Instruct: Classify a review as either positive or negative.
Query: revised replacement

I have an elite model that is over 4 years old. Guess they redesigned these. The original felt aa little stiffer when new & softened over time. These change color to tell you when to replace them. I just do it after every 6 month check up with my dental hygenist. They fit fine, work fine, feel fine. Not much more to say about them.