Fit well, feeds well. Reasonable price. Happy with the purchase.

So, really wanted to like these. They appear well-made, are robust, and just plain cool. However, they suffer from two problems, one minor, and one a deal-breaker. Firstly, the spring is incredibly stiff. So much so, that when I first got them, it was literally impossible to hand-feed past the 5th round (Glock 43x 10-round capacity variant), and the use of a speed loader was absolutely necessary to fill mag to capacity. That being said, I filled the mag, let it sit, and emptied/refilled it every 24 hours, and after 4-5 days, I can now fill the mag entirely by hand, albeit with the 10th round still being pretty tough. So who knows on that--perhaps the spring just needs some break-in time. Secondly, a full mag will NOT freely release from the the gun. Consistently. Pressing the mag release button results in the button just staying depressed with no more travel, and you have to manually rip the mag out of the well. I showed to one of our firearms examiners at work, and we both determined this was due to obturation of the mag from the pressure exerted internally from the cartridges under tension from the spring since there is no metal reinforcement to offset that like in OEM Glock mags. Other than that, they operate as normal, but for a self-defense gun, due to the second issue, they will very unfortunately be relegated to range use and manipulation practice with dummy rounds only, rather than EDC.