Apparently magazines are a lot more reliable than I thought…. may add more to this later but here are some good sources of info.
Magazine spring madness: ‘creep’ to your ‘elastic limit’ to un-earth the urban legend of ‘spring-set’
American Handgunner, May-June, 2003 by John S. Layman
THR, Mag Spring Life
THR, Am I wearing out my magazine spring?
THR, Mythbusters: Keeping magazines loaded long term