M&P40.
My Glock has been having "issues", but I think I just discovered that it's the extended slide lock being pushed by my hand. The gun came with it, so I'll be switching to a stock slide lock, then we shall see.
My m&P has around 5k rounds through it and 0 malfunctions (one ruptured case).
Edit just to verify glock issue confirmed to be extended slide release.
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