I don't think that any one person's experience, especially mine, will settle a discussion like this. Everybody's training and experience levels are different. Every armed encounter is different. Tell me what your next gunfight is going to be like, and I can tell you whether or not a mag safety MAY be helpful. Otherwise...

I never shot my gun to slidelock. I knew about how many shots I had fired. I did a tactical reload before holstering without thinking consciously about it, but the shooting was all over by then. It was likely a result of having had excellent instructors over the years and forming what I hoped were good habits.

I think that the kind of unintended disharges we are talking about here, and whether a mag safety would have helped prevent them or somehow may have contributed to them occurring, can't be settled for sure. Guns are dangerous. People shouldn't handle them without training. But, they do.

As someone once said, it is impossible to build a foolproof device because fools are so ingenious!

When a local department, the Salt Lake City P.D. issued Model 39's in the 1970's, an officer I knew was saved by the disconnect. He stopped a group of gypsies who jumped him, got his pistol away from him and beat him. He carried it with the safety/decocking lever in the 'safe' or down position, and during the process of trying to make his gun go off, they ejected the mag, which bounced under their car so they couldn't get at it. Luckily, they gave up trying to murder him at that point, throwing his gun into a roadside creek and leaving him.

I prefer that my handgun have some kind of manual safety device, to slow down the actions of someone else getting their hands on it, but I seem to be in the minority, judging from the popularity of Glocks and such.

If it were possible to PROVE that a mag safety was good or bad, it would have been done years ago, and all handguns would either have or not have them. But, every situation is different, every gun handler is different, and every gun buyer has to decide for themself which features they want. One can make good arguments for both positions.