If all you were going to do is plink on weekends, then either brand of revolver, Pietta or Uberti would do just fine. Since you want to throw cylinders into it, then you better head for the best quality revovler you can get. I don't even know if the Pietta allows the conversion cylinder. I have a Pietta and it is a good shooter. I shoot 30 grains of APP 3f and a .451 roundball. Out to 25 yards, plenty of power and lots of fun. I small game hunt with it, but that's about it.

Since you want the conversion I would go with the Uberti and in a New Army model that has a top strap. All steel frame, no brass is another thing to look for. The top strap helps the revolver to keep from stretching if you happen to chain fire it. I know, I ruined a Navy that way. It chain fired and stretched the frame. I had it fixed but never trusted the thing after that.

Some other brands to consider are Ruger, and Colt. Both of them make excellent revolvers, but you will pay for them.