The swager has proven useful for me on many occasions. It is not a piece of equipment I would use all that often, but very handy when you have a bunch of brass that you cannot fit the primers into. For me, I found it most useful when I was loading federal 9mm brass. Sometimes hard to tell from looking at it, these pieces of brass are near impossible to get primers into them. I found out the hard way on my 550 when trying to seat a primer, and the damn thing crushed and exploded. Since then, I have always checked the head stamps of all my 9mm brass before loading, and tossed the federal brass to the side to be swaged. Good thing is that you only have to do it once. In a nutshell, the Dillon swager is a good piece of equipment.