Ditto what all of the previous posters have stated.

I'll probably receive alot of push back for the comment I'm about to make, but the only safety on a semi-auto pistol that makes any sense (to me) is when it's on a 1911 style pistol, i.e. "cocked and locked"/Condition 1.

The 40c like many of the other M&P semi-auto pistols, is a double action (DA), striker fired pistol (i.e. no hammer for SA). There have been many previous posts about the pros & cons of manual and mag safety equipped pistols, and whether or not there should be a round (ready) in the chamber (Condition 1 for a striker/DA) that you can search for on this forum. Also, there is a plethora of posts related to round/caliber "power".

My preference is no safety and pistol in the "ready-to-fire, just-pull-the trigger" condition (1).

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MotorCityGun