Damn good magazine. Can fire 2 1/2 mags worth of BB's. So you'll reload twice before you change C02 cylinders. They are solid, heavy and long. Make a gbb feel dead real. Be careful when you hit the mag release. It'll plummet if you don't catch it. The spring at the bottom has a chance of completely firing out and breaking if you aren't careful. My permanent fix. Wrap the bottom part right above the button with electrical tape TIGHTLY! It'll 100% fix that problem. I did it to both my magazines and have zero problems since. Mags hold more then 30 bb's. C02 is easy to change and close. Wouldn't recommend leaving the tool sitting on the bottom during a match. It could fall off too easy. Create friction to prevent slide off or keep it in a pouch.
Good compression/seals/no leaks
Super freakin solid!
Heavy as a lead ball
Bad design on bottom easily fixed with electrical tape. Basically spring has a chance of firing out of the bottom.
Tool on bottom can possibly fall off eventually and render your mag annoying.