This capo works just fine. The first time you need to adjust it a little bit to fit on your guitar, and after that you can use it at once.
When it is adjusted properly, the strings will not rattle or anything, it is a serious capo, even though the price might make you suspect otherwise.
In comparison with a clamp style capo, the disadvantage is that you can't place it on your guitar when your NOT using it. But I guess that's only a handy trick when you're on stage, at home you can grab it whenever you want.
For the money, these are unbeatable of course.