Howdy Amsdorf,
The 84 is a very well made handgun and back in the "Day" it was standard issue for many police forces in Europe. Also was the sidearm of several officers in various militaries in Europe.
It was very popular back before there were any of the subcompact and pocket 9mms on the market. Nowadays would be hard for me to justify carrying a handgun that was that big and heavy while only firing a .380acp round.
Heck, most of the gun newbies do not realize that expect for the Detonics Pocket 9, there wasn't a 9mm available smaller than a S&W Model 39. Several small companies, like Devel, modified the S&W 39 by shortening the slide/barrel and the frame into a pistol the size of the 3900 Lady Smith 9mm. Even though I'm not a 9mm fan I carried one as a BUG for several years because it was the smallest semi-auto on the market that shot something more powerful than the .380acp.