I have used the RCBS swaging die and it works as advertised, still have it.
But I wanted to change to a stand alone device for various reasons. Mainly I could mount it and leave it, not tying up a press.
I bought a
Dillion Superswage and a
RCBS bench mount swage tool..
Plenty of links to them in the above discussion. Added links to the two swagers.
I figured I'd try them both and keep the one I liked.
I kept the RCBS bench mount because I liked the ergonomics much better. It can be mounted most any where on you bench, whereas a Dillion Superswage has to be mounted at the edge of your bench as the handle operates like a press. If mounting the Dillion on the end of a bench parallel with the bench length, then it could be worked very comfortably. But the ends of my bench are not acessable so the dillion had to be mounted at a 90 degree angle to the length of the bench. To me this was a uncomfortable working position, but certainly usable.
The RCBS bench swager can be mounted most any where, so I mounted it to my bench about 3 inches from the edge parallel with the bench length. This way I can set in front of it and operate it with both hands extended about the same distance. The handle operates in an arc level with the bench. Very comfortable, IMO.
I sold the Dillion and kept the RCBS, but it was a personal preference, as both devices are well built and do the same good job.
I think if you have a lot of brass to swage, the Dillion or RCBS bench mounted swager is the nuts. But if you have just a few hundred, a swaging die might fit your needs better and be more cost effective. YMMV
Edited to add links.