This works great with Numatic's Henry-style vacuums on hardwood floors and low-pile carpet and rugs.
It is more or less useless on shag carpets and rugs so if that's your thang, you need a different solution.
I tried this on my Shop-Vac as well with mixed results. This is only an attachment so it's performance is going to be limited to what your vacuum is capable of. The suction of your vacuum is what turns the brushes in the attachment so, if your vacuum isn't strong, the brushes won't turn with enough force to make them effective and you'll be dissatisfied.
It should also be noted that if you have pets or are sensitive to noise, using this attachment will make your super-quiet Numatic vacuum significantly louder. The noise from the brushes turning in the head was quite a bit louder than the noise from the actual vacuum. However, if you have a louder vacuum, the noise of the brushes in the attachment will probably go unnoticed.
If you are looking for a non-powered floor attachment for your Henry or other suitably powered shop vacuum, this is a solid choice for the money.
Note: This performs identically to the Airo Brush that Numatic sells. They're the same size, they seem to be made of the same materials, and they work in EXACTLY the same way.