45
For the price the Pederosoli in 45/70 or 9,3x74R is a good rifle. My brother had one in 45/70 and o shot it quite a bit. i have also shot another posters a few times.
For use in the USA it is an excellent choice.
For a nitro Express calibre double I recommend you look at Chapuis, Krieghoff, Merkel, Searcy, Blaser, and Heym.
Pick the one you like the best.

A Chapuis in 9,3x74R [scoped] makes a gread medium bore double, suitable for all North American game. I have one and like it a lot.