Yeah, I did a bit of research and I second this opinion.I would just avoid them all together. The reason being that there are not really any safety regulations for these items, and they can contain lead or other harmful substances (glues, dyes, etc). The wire on the inside of many is also a concern. They could also easily eat pieces off. The only type I might contemplate getting would be those made for terrariums, but I think a better solution would be to make your own sleepy plant from fleece fabric, or other safe items.