But I'm not really satisfied, for the following reasons:
You can not really see from the photos, but protection "around" the power button and volume for the power button it means that it is a little harder to reach (the volume of the plastic support a troublesome bit access - careful if you have big fingers), and that means above all that they are badly scratched when installing or removing the phone from his protection ...
If you think you keep your phone in its continued protection that will not be a problem, but if, like me, you remove and replace the phone regularly, then I minquiète some of the influence it has on the volume buttons power in the long run ...
[EDIT] with a knife it is quite possible to cut the clipping that the power button and the plastic part lying above: the phone is still well fixed, but is much easier to install and remove. So I added a star for those who are willing to do this hack (which literally takes less than a minute).