In defense of eight round magazines, I have four Chip McCormick ones, that are nearly twenty years old.
They still have their original springs and have had many, many thousands of rounds through them.
And they just work.
Not only in mine, but for many others that I've loaned them to.
(New folks at the matches never seem to have enough mags for those long courses of fire).
Lock the doors, they're coming in the windows.