Stan, I don't know much about the source of reliability complaints on Red Labels except that every time the gun is mentioned on the web, somebody brings it up, usually somebody who has tried them as a trapgun.
My own actual experience mirrors the remarks above; Red Labels need a longer stock for those of us blessed/cursed with "ape hanger" arms, and they basically are all "duck/turkey/coyote" guns--fine as long as you don't have to pack them very far.
The 28 is an exception to the above, and I wonder if Ruger would ever make a 20 on the 28 frame? Or make a 20 with an alloy frame--certainly Ruger has the technical expertise to do that! (Of course then people would gripe about the recoil with 3" magnums.....).