If he makes them the way Bob Dozier does, the sheath will split apart when you twist (laterally, not rotationally) the light and the light will slip out easily. Kydex is terrific for the Dozier knives I own, even the folder.
$9 seems like a lot of money, but it will save a few pocket repairs, I suppose, and maybe pay for itself that way.
Key scratches? You were joking, right? This thing abrades brass keys and the 'scratches' are actually key blood seeping into the knurls...