I have the Swage-It for the Dillon 550 and 650 and like them. I use them for bulk processing 5.56 and 5.7x28 brass. While I will end up with a few cases that are still tougher than I'd like to seat a primer, for bulk brass processing they are a thumb/time saver. Just like anything, if you put too much effort into it, you're going to break shit. I see no way this thing is going to break my press, so long as I make sure the mounting bolts stay tight, the brass is lined up properly, and I don't try to force my way through a tougher push...say from a primer that got torn and left the sides of the primer in the pocket.