I had a vintage Security Six with a 2.75" barrel. Its advantage over the SP101 was the extra round. Its disadvantage was the DA trigger pull and its weight. I think a recent critic was right: the Security Six is really a single action revolver capable of being fired double action. The comment was meant in jest but the SP101's trigger pull is much better than the SS. And, the OP I think was concerned about weight. So between weight and trigger pull...I left off my SS.
If the weather is cold enough(read: more concealable) I sometimes carry my N-Frame Performance Center Model 627. Certainly not easily carried concealed but it is singularly the most accurate handgun I've ever owned. I mention this because I am equally enamored with both S&W and Ruger...LOL.