I know Kai Domain sells not only C8 flashlights but also just the C8 drop-in for a little less. I have a few C8's, so I like the idea of buying just a pill with the driver and LED installed instead of paying for a whole new light. With the BLF A6 driver and a XP-L on a sinkpad, wouldn't that make a great C8 pill? How hard would it be to set something like that up? It's not as profitable as selling a whole light, but it gets rid of a lot of the variables in workmanship of the light that might turn some people off.
You would have to have a C8 host with a Reverse Clicky switch, or you will play hell trying to work the UI.
-Chuck