Review (4/5): they're a bit bulky for the mouth
There is a lot of bamboo around the bristles so the toothbrush head feels large and clumsy. I guess you can get used to it but it's a bit of a learning curve. The bristles are not recyclable or biodegradable so you need to pull them out to discard the bamboo, but I'm willing. I will probably end up using the bamboo in my fireplace, rather than trying to compost it.