Hammerdown - it sure does sound like you got one that slipped through. But how does it work since you got it back from S&W? As you mentioned, this is not the first time S&W has used screwed in barrels with shrouds but they have sold an awful lot of the Scandium revolvers.
According to the adds, these are L and N frame revolvers. Even the j-frames are strong enough to do what they are required to do and this series ahs the strength of the larger frames. The frames are Scandium and the cylinders are stainless steel. I would expect the finish to be bead blasted, jusding by the look of it. The S&W rear sight has been replaced by a Cylinder and Slide Extreme Duty fixed rear sight and a Tritium night sight up front. They come in 38, 357, 44 Spl , 44 Mag. and, 45 ACP. HTH. Mikey.