It depends
 

It is handy if you are shooting with a tripod and you don't want to be tethered to it by the FireWire cable (which is what would happen if you put the FS-4 on your belt). But then, I would definitely use an external microphone placed away from the camcorder.

Excellent point Andrew. I was wondering the same thing. It is quite noisy. A mike anywhere near the camera may pick up the noise. It comes with a belt clip that could be useful. I haven't tried mine either way. I just took delivery of an XL2 and will try it shortly.

Has anyone tried it mounted on the camera?

John