I have a list of guns I want to own and shoot and enjoy in my life time, and generically "a BP pistol" and "a BP rifle" have been on the list.
Kinda fell into a heck of a deal last year on a Uberti made 1858 clone, and then just two weeks ago fell into another deal on a CVA Lynx .54 side lock percussion rifle.
Quite happy with the pistol, though I still kinda want a Kentucky/Pirate style single shot big bore as well. Or something like a parlor pistol in 32 or 36 caliber.
For the rifle... VERY happy considering what I got and what I paid, but if I had taken the time to think and do research I'd be happier long term with something with a wood stock and probably .50 vs. .54 only because of the larger variety of projectiles available in general and availability period locally. Also still have a hankerin' for a small caliber (32 or 36) squirrel gun/plinker just 'cause I like small light calibers in general, even with my cartridge guns.
Accessories - wish I had thought ahead and bought some .54 felt wads cheap when I was ordering some stuff but such is life. Regret the $6 starter (broke on second use) vs. the $7 starter (plastic vs. brass, brass seems like it is simply a hunk of range-use ram rod/cleaning rod w/ a handle, should last). Still working on range box/possibles box for BP stuff.... but that is just self-organization.
Accessories I love - bought a bunch of 3ml plastic test tubes with flip tops that snap shut. Premeasure 30gr or 60gr of 3Fg powder in them. Pistol gets a 30gr in each hole, rifle gets 1 60gr (pussy cat) with an extra 30gr (hey you're shootin a 54!) or a second 60gr (max load, haven't gone there yet). No way shape or form of traditional but quite convenient and easy to use.