A friend sold me a Colt that had the mag loaded for a few years. It did fail. It would not feed correctly. It work well for him before he loaded the gun and put it up. I replaced the mag with a Wilson. I don't even keep the Wilsons loaded all the way either. I noticed one Wilson's advertisements mentions something about being able to be loaded longer periods of time then other mags and still be reliable.
This question comes up often I have noticed, and it is always subjective.
