Upload & Sell: On
The latest Hawk's Factory helicoid has an adjustable infinity lock so you can set a hard stop infinity for any adapted lens. It's also well baffled and doesn't cause vignetting on 135 and longer lenses. Unfortunately, I had to send mine back (it had a little up and down play on the camera mount side with both my a7 and a friend's 7 and 7r). I'm going to wait a few months for a new production run and give it another shot then.
In the meantime, I found a Summicron-M 50 v5 at a price I couldn't pass up. It's the only Leica M lens I own that was manufactured in this century (this decade, even). I've had a couple of v3's that were good, but I wanted the updated optics from the 1977 redesign but didn't want the focusing tab of the v4. The built-in hood of the v5 is just gravy.