Well.......do ya?

Always wondered if I should store them loaded.....same for the C-prods I guess too.

i have all my magazines loaded, doesn't matter what weapon it's for it's loaded

This  guy   is smart

Springs don't get weak from being compressed.  They wear from compress/expand cycles.  Leaving a magazine loaded is no problem for the magazine.

I keep all mine loaded as well, but only to 30rds so I can seat them on a closed bolt easier. Haven't used Metalform yet, all I use is ASC and they have been 100 percent. The only unloaded ones are the two C Products that suffered broken springs during the FIRST loading lol.

It's the compressing and uncompressing cycles that fatigue springs, leaving them loaded is fine. I only buy NHMY and Magpull M3, Glock and Metalform never had a single issue with any of them. Granted my 1911 only fires about 300-500 rounds per year, but every Metalform magazine ( 5 ) functions flawlessly with all hollowpoints, semi wad cutter etc. ammo I have tried in my Springfield Armory 1911 R.O. Which would be 200 gr Speer Gold Dot +p, 230gr Speer Gold Dot, 230gr Federal HST, 180gr Winchester Semi wad, 230gr Winchester, 230gr Remington, 230gr handload RN plated.

There are some mags I don't leave loaded, usually anything with a polymer lip stays empty except for my PMAGS since they have 'dust covers' to take pressure off the lips. 9mm AR SMG mags would be the last type of mag I'd worry about leaving loaded, they are stout.

I only load mine to 30 rounds too but it's mostly because my OCD would never let me have an odd row of ammo in the box.