Slickest-
Never owned a Buckmark, but had a Friend in the early 80's who did. Gun was in-accurate, about 4 inches at 25 yards with a scope. Not a tree reat head shot gun. He sent it to Browning, and they sent it back stating it was within accrracy standards. Kind of soured me to the Buckmarks series, though I know one sample from 25 years ago is not an accurate representitive of the line.
I have 2 heavy barrel Ruger Mark 2's, one with a scope, and one without. Both are more accurate then I can hold, and have accounted for more bushytails, rabbits, and tin cans then I can count.
Again, never owned a Smith 21A, but I have a heavy barrel model #41 target auto. It makes a decent shot look great, has the best trigger I have seen in a handgun, and that beautiful Smith high gloss blue. I don't know if they are still made, but a nice used one is about $600 in this area. I always wanted to really see what mine could do, but never had the guts to drill it for a scope.
Larry