Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Glow in the dark plastic is shoddy - stick to other colors

There is no doubt that Magnetix are a great toy. And you can never go wrong with glow in the dark - or can you? The plastic used in these Magnetix is terrible. They develop cracks at the end that allow the magnets to pop out. I had to glue one back together right out of the box. At least 7 more pieces have failed after just 2 weeks (and many more have visible cracks). This product has terrible quality! We have several other sets in other colors and haven't lost a single piece to this problem. Stay away from the glow in the dark set!