Inevitably it beeps. Then I get the irritation of having to spread-eagle front and back for the security people as they wand me back to front to see what sort of carefully concealed weapon of destruction I may be carrying. To date, I have had to revmove my shoes three times and have them scanned separately. I have had my ankles carefully checked for concealed weaponry. I have had my butt and crotch inspected (from outside the clothes, you perv's) for "non-ordinary" equipment.
To date I have yet to be found smuggling anything more untoward that Denver Hayes shorts or Happyfeet socks through the airport check.
Its irritating. It bugs me that I have to go through this every damn time I fly because something about my body makes the metal detector beep. Nothing starts off a trip on a happy note like a near-strip-search and a quick check of my jewel-pouch with a detector-wand while other annoyed travelers stand and watch in increasing impatience.