The older S&W revolvers had more attention to detail and were more expensive to make. Features were pinned barrel, chambers recessed for cartridge rims, extra screws in the frame, wood grips with better checkering and "diamond" surrounding grip screws, forged or milled components. Newer guns do not have them making them cheaper to make. Manufacturers refer to such products as more advanced designs.
If you have guns you haven't shot or taken out of safe for long time now is a good time to sell. People want them and laws aren't strict enough yet to makes sales between individuals more difficult or impossible. If you hold on it might be more difficult to sell because as Michael Moore said it is still possible for Trump to win re-election.
