I have an M83 and an M79 that I occasionally shoot in matches. The M79, in particular, gets a lot of odd looks and questions from other shooters. For some reason, if people aren't familiar with a gun, they seem automatically convinced that it is a double-action and not allowed in matches.
As far as shooting, I use my standard .44 Russian black powder loads and have no problems. All of the Reichsrevolvers I have ever handled have VERY strong mainsprings, and that, coupled with the loonnnggg grip and short hammer spur on the M79 makes it a two-hand proposition. I tried to shoot one-handed a few times and my hand started cramping up from the immense effort.
These revolvers don't have ejectors--you can remove the cylinder pin if you want and use it to poke out the cases (I think that was the original intent of the designer) or you can do what I do: I have a short brass rod with a loop bent in the end that I hang on my belt so I can use it at the unloading table to poke out empties without dismounting the cylinder.
These guns are built like tanks and are a hoot to shoot. Their only weaknesses in my mind are the safety (yes, they have a safety lever) and the cylinder pin retainer (on the M79). Both of these employ external flat springs that are somewhat fragile and exposed to damage. After so many years, I often see guns with them missing or broken. I would avoid using the safety and be very careful with the cylinder pin retainer, because replacement parts for these are very very difficult to find and because of their odd design, difficult to repair or make replacements for.
So, have fun and let us hear how your shooting goes.
--DJ