I've never owned a cap-and-ball revolver, but have had some experience with them. They are interesting.
Shooting blackpowder, get used to the fact you will seldom, if ever, see your bullet kick up dirt upon impact. The smoke obscures that. Also, get used to dirty, sooty hands after a few shots. And, fellow shooters tend to avoid shooting next to you at the range. The aroma is, um, well, pungent. There are blackpowder substitutes, of course.
You will be amazed at how much smoke can be crammed into the revolver's chamber.
Fun? Yes, indeed. You might be tempted to load some cartridges with black powder. By all means yield to this temptation. Especially if you have a good Ruger Vaquero or Blackhawk in .45 Colt caliber.
I had a friend many years ago, in the Army, who had an original Remington 1858 Army Model set up with a precision barrel and target sights and he did very well in competitions.