Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Plastic doesn't work

I've been using my egg poacher for several weeks and have one big complaint: the egg cups are made of plastic which is non-conductive of heat. The egg cooks from the top down using the steam in the pan. When it seems done I find that the top is done but the bottom is runny and water has collected on top. I damaged one of the cups one day - it got too close to a burner and melted - and substituted a metal one from an old poacher. I was amazed how fast, and how much better,the egg poached in that cup.