Alpinex, I agree. And thanks for the correction as to the dates.
I believe that Uberti makes a more "authentic" replica, in that Pietta sometimes varies some of the shapes of certain parts.
Here's an authentic 1860 Army:
And here's a Pietta 1860 Army:
Note the profile of the barrel just behind the wedge, in the area where the arbor would enter the barrel piece. See how on the original it's smoothly curved, but on the Pietta the piece is squared-off?
And also, Pietta comes up with some non-authentic guns - those that were never originally made - such as .44 caliber 1851 Navy's, for instance, or that recent 1860 "Sheriff" revolver that Cabelas is selling.