The recoil spring is so strong that I can hardly wrack the pistol. My wife can't even nearly wrack it. I find that the last 1/4" of the slide is almost impossible to get - it is like the springs are "bottoming out". I have to jerk real hard to get it to catch the slide lock and then have to...
My wife got a new 638 about 2 years ago and it would fire sometimes. The firing pin was barely denting the caps. I took it to the S&W repair man for Texas and he replaced the part while I waited. He said the firing pin was too short. We shot it and it did fine. It is still shooting every time...
I like Shield
I like my Shield. I would not worry about shooting one if you use the proper ammo. See if you can find a Shield owner and shoot it and see how you like it. My son has one also and he likes his. S&W will stand behind their guns parts.