I've got a SeeAll on one of my crossbows.
It shoots 380fps, and the sight holds up well to that vibration. There really isn't much to it to go wrong. Other than the base, everything is really light, so I doubt anything is going to be prone to bouncing around. I've had it about two years with no problems encountered. If it'l stand up to 9mm, .40, .45 caliber hand guns, it'll surly stand up to the light vibration of a pellet / BB gun.
They make a couple of versions now. If you are interested, take a look at their web site.
Mike