I have a Medalist and two Medalist II cameras. They're awesome. I LIKE they use 620 film. Hand respooling is no problem for me. If they were 120 film cameras, they'd be much more in demand and prices would be much higher.
I wish the primary viewfinder window was a bit bigger, but I love that it's separate from the rangefinder window and I can see them both by moving my eye slightly without moving the camera. The viewfinder is just glass and the rangefinder is just prisms and glass. No semi-silvered mirror to degrade with age. After the glass and prism are cleaned properly, the viewfinder and rangefinder are as bright and clear as they were when new. The viewfinder has some magnification and a fairly wide base, so it's dead-on accurate for the 100mm lens.
I'm fairly certain the Medalist II focusing helicoil is anodized, just as the Medalist was. The only difference I can detect between the two is Kodak didn't dye the Medalist II helicoil black during the anodizing process. Anodizing aluminum produces a very hard surface and the Medalist II passes a simple scratch test. (I'm not going to gouge it with a sharp knife, but the pointed tip of my multimeter doesn't scratch it like it does regular aluminum plate.) The better test is conductance. Anodizing produces a non-conductive surface and my Medalist II helicoils are non-conductive. I prefer the look of the black anodizing, but you're not giving up durability there with a Medalist II.
The lens coatings available when the Medalists were produced were very soft and unsuited for external surfaces. I think the internal glass/air surfaces were coated with the softer coating, but not the external front or rear lens surfaces. By the time the Medalist IIs were produced, Kodak had the more durable lens coating available and those lenses were "Luminized" and marked with the circled "L" on the front. Otherwise, the lenses are the same.
Both models are easy to load... once you know how. They require a specific sequence of steps. It's pretty intuitive once you've done it a couple of times. They're not fragile cameras as long as you don't get a ham-fisted, "I know cameras" attitude without reading the manual once through.