My JMCK came yesterday. It's sized for a G17 but expect to carry my G19 most of the time. I am very impressed by the build quality and the design. The craftsmanship is at least equal to my Raven.
So far it's very comfortable, but since this is my first journey into the land of Junk Carry, it will take some getting used to. A few observations:
I'm very glad I got the longer G17 size because it helps stabilize the holster. How high rise the pants are makes a big difference, and will be a challenge in some cases. My Dickies sit fairly low and the fit of the JMCK is good but with 5.11s or Vertx which are higher rise, the gun seems too high in my belly and digs in the groin. I'm still figuring out what belt to use. My Ares Ranger belt isn't easy to make work, and I'm finding I don't need the stiffness anyway. The snap loops are great. I couldn't make the split loop work for me.
Some pictures follow. Apologies for the bright white tummy...