When these magazines arrived at my house, I took them all out of the box and immediately lubed them. I tested each mag and had problems with them not feeding, so I lubed them again and they were slightly better at feeding. After several uses of each magazine, I've found that they take a little break-in time and lots of silicon oil before they really start to shine. After they break in they feed flawlessly and they are very sturdy and tough for plastic mid capacity magazines. One thing I should note though, when you lubricate them the lubricant will tend to seep through the bottom of the mag and on one of the edges, so I put a small amount of superglue on these edges and it solved this problem. These mags look great, they are a nice shade of grey that contrasts well with black, they are sturdy, and they proven to be reliable even after being thrown on the ground and such. Overall, good mags for the price, but take a little effort to get them working just right.
Very strong plastic.
Reliable (after breaking them in)
They all arrived working.
Didn't work well at first (at least for me, but was easily solved with lubricant)
A little leaky after lubrication.
Nothing else so far!