I was a fan of the old discontinued polymer TAPCO Intrafuse rail because it was a lightweight polymer and the screw was captive.

Too many of the ones I've seen now have a screw that is loose, and requires you to hold the screw in place with a screwdriver while you install the thumb nut on the bottom.  I guess these are made with the idea that once it's in place, you leave it.

Well, I want one that I can attach a red dot to, and just remove the mount and everything when I'm not using the red dot.

Suggestions?

I believe the ARMS #02 is what you seek.