screw the custom molds. use a standard telex 5x5 ($230 or so) or plantronics MS50 ($140) in ear headset with boom mic, buy a "Y adapter" ($20) to add a second ear piece so you can have sound in both ears like the Mach 1, poke a large hole into yellow foam ear plugs (FREE) and slip those over each ear piece (Comes with headset). you will have the quietest most comfortable in ear headset youve ever owned, and just change out the ear plugs every trip or whenever. very cheap comfortable TSO'ed alternative to the Mach 1