Well I finally had a chance this weekend to run my pro mags in my S&W 469.
First of all, they look nearly identical to the factory magazines, save for the length.
The followers have no discernible difference and the body of the mag is very well crafted, TIG welded steel. Being brand new, the springs were pretty tight, and loading the last few rounds of each was a pain in the thumbs. Because of this, I was expecting some double feeds. Anyway, weather and work interfered and I wasn't able to shoot them until this weekend.
First up was the 15 rounder, loaded with TulAmmo.
Started out with slow, controlled fire, about one round per second. After the mag was empty, slide locked back as it should. The mag ran flawlessly.
Then I loaded up the 20 round mag ( filled with WWB), dropped the slide and continued firing, about 1 round per second. 20 rounds later, slide locked back, the mag ran flawlessly.
Loaded each mag again with WWB. Went for some double taps. Each mag ran flawless.
Loaded up again for some rapid fire mag dumps. Not a single hiccup.
No failures of any sort. Granted, three sets from each mag isn't any qualitative study on how well the mags would operate, but they beat the expectations i had based on the thoughts on other pro mag products. These, however, worked perfectly. I'm pleased so far. I'll run at least another five sets or so through each prior to carrying them, though, just to be on the safe side. But it's doubtful the 20 rounder will ever see daily carry. The 15 rounder fits in my Blackhawk mag pouch right next to my Leatherman Surge, so it'll get carried.