The magnets are not very strong. When you try to build a 6x6x6 cube, you encounter problems. For example, if you build a circle with 216 pieces and then try to connect them in 2 lines, you will find that the two ends do not connect like the middle balls do. Nevertheless, it is fun, worth it.

Although smaller than expected, they are quite powerful magnets and well-made. The little one spent hours making constructions.

In my opinion, they are very expensive for what they are (maybe I'm wrong because they are quite powerful magnets), but the kids enjoyed them. If they were cheaper, I would buy another 5 packs. I give it a 4 due to price and size.