Well...
high on my list would be a good magazine because they are the achilles heel of any pistol
I grow tired of the debate over which recoil spring to use and I'm pretty sure many pistols have been rendered useless by folks changing springs to
upgrade a pistol that was doing just fine anyhow. I've often said that those who advocate frequent replacement happen to sell springs.
In fact "upgrade" has become a trigger word. If some of the other boards are an indication because so many just can't leave well enough alone. If the gun works how can just changing parts be an upgrade if it still works when they are through messing with it. Of course this is a great business builder for folks who sell parts.
Equally wearisome is the fuss over MIM parts by people who only know they are different and, therefore, obviously inferior. But if they failed at the rate alleged by folks who wouldn't know one if it hit them over the head...
So how's that for a start Kevin?