I'm sure this thread will be moved to the Black Powder forum before too long......
I have a Pietta brass frame 1851 Navy in .44 cal; purchased from Cabela's about 6 months ago. The price for the gun only was $89, but I also got the accessory kit; I believe the price was about $120 or so. I've had it out to the range 3 or 4 times now, shooting about 40 to 50 rounds per trip. I've been using Pyrodex.
The gun works OK. Was not impressed with the kit I purchased with it, and have pretty much re-bought the individual components.
Using my 55 year old eyes, a 20 grain load groups to about 2.5 to 3 inches at 15 yards, resting on sandbags. It shoots about 8 inches high, but I understand that's normal with this type of gun.
Spent caps cause more jams than I would like, but again, I think that's just part of the nature of the thing. I've since bought a Ruger Old Army, and it's much better in this area. Of course it cost 3 times as much.....
The instructions said that a 20 grain load would be the best. That's relatively mild. If you'll want to shoot something more potent, then you'd probably want a steel frame (Pietta makes them, too), or maybe move up to an Uberti or the gool 'ol Ruger.
Hope this helps,
Ken.