Kukri, I have two OM .357's now, have owned many more OM's in the past as well as have owned various NM's. FWIW here are some observations; Stainless is all steel as mentioned above - but is heavier for carrying in a holster, but more resistant to rust and visible holster wear. The Blue NM version has the aluminum grip frame and ejector rod housing and handles more like a Colt SAA, but not exactly. As for durability, there is not a better affordable SA handgun on the market - in any of it's versions. If adjustable sights are not a requirement and you want an all steel blue gun you can go with the Vaquero - same gun, different sights and parts. One thing I can tell you - they will shoot forever with reasonable loads (anything up to factory max). The Wolfe Spring kit, about 15.00 from Brownells, will really improve the hammer and trigger - I use the Wolfe 19lb mainspring and have never had a primer fail to pop (even hard CCI's), but a buddy of mine used the 17lb spring and found it a bit too light - he went to the 19lb and that cured his problem. Enjoy, Odessa