If you have short thumbs and if you can keep your thumb off of the slide release during shooting, they are really nice.
Releasing the slide with your right thumb is EASY with that product.
I took mine out of my XD-45 though, as I kept resting my thumb on it while shooting. My slide wouldn't lock back because of this.
I find myself doing the same thing with my XD-M now and I sometimes thumb the slide release up too, causing the slide to lock back when I DON'T want it to.
During my next practice session I will work on changing my grip to stop this.
(Let my right thumb rest on my left thumb, instead of up against the gun)
Kind of regret getting rid of it now...