IMHO, the ruger security six is the best wheel-gun ever made for self defense or a walking around in the woods gun. The GP-100's are nice, but very heavy, something that is really best for use as a target/competition gun. The security six is even a little on the heavy side for an everyday carry gun, so mine is reserved as a self defense piece at home, or as a finishing off piece during deer season.
All things considered, these would be my primary carry choices: for larger hands, Glock 19, 23, security six, S & W M&P , for smaller hands, easier concealment: Springfield EMP, Glock 26,42, M & P shield, Ruger sp101, Taurus 85, Small frame S&W revolvers, Khar arms (.380 & 9mm) many models. Ruger LCR, LCP, LC9.
I excluded haevy guns, such as 1911 types except the EMP, which is a miniaturized 1911 scaled down to 9mm & 40 S&W. My choice would be 9mm in the EMP because of the alloy frame. I also excluded the small keltec pistols because of thier very heavy trigger pull.
My 2c.