Well I abandoned the set screw design when I first started reloading in 1975 and just reset my dies every time I used them . This was ok cause I only had a couple of rifles and one 41Mag Black Hawk. When I discovered the Hornaday crossbolt design I converted all my dies for use in my single stage presses to this design. In my turret press i use the older Lee lock rings without the o'rings and i use two lock rings to lock the die into the turret . In other words I double nut the die because it stays in the turret . I recently bought some of the new Lee cross bolt lock rings that come with their little "spanner" wrench and I am trying them out on some 357 Lee dies . These are aluminum which I like but they too have an o'ring which I don't like. So I have been installing them in the die with the o'ring side face up and removing the o'ring . I don't know how well the little "plastic" spanner wrench will hold up but it does allow you to snug the die up which I think is a benefit. Just thought I would see what you guys are doing and get your thoughts