UPDATE...UPDATE...I have deleted in my posts above references to the Galloway kit causing premature slide lock back with rounds still in the mag. It doesn't do that. I DID THAT! As I have been doing more testing between the 2 kits, installing/reinstalling trigger springs, I noticed that it is possible to not get the slide release spring/tensioner in the correct position. I refer to it as a "tensioner" because it is not shaped like a spring per se. One position has the tensioner barely seated against the removable upper/forward rail component. In this position, this is what caused my premature slide lock back. Reinstalling the slide release so that the tensioner has more of a "bend" or angle as it rests against the upper/forward rail component is apparently the correct position. This allows the slide release to be under the proper tension. The difference to the human eye is subtle, especially mine. Anyways, fired many rounds and nary a problem.