We don't realy have that problem, there used on are hmc so they tend to hang in place. I guess you could recess them but then you would probably want your part recessed a little deeper then the tiny vice, they seem to work best when clamping the part as high as posable. There are some parts that we make that spacers are put under the clamps to rise them up so they hold a little better. On a side note,the only problem we have had is having to replace bolts becouse the hex it the bold became rounded.
Just push the button,what's the worst that could happen.