Well, I'm not sure what you mean here. The Cimmerron 7th over time has been made by both companies. Each was tasked to make the weapon with the proper markings defined by Cimmeron. If it is a Cimmerron 7th, no matter what the manufacturer, it will have the proper markings. Some of the early Uberties had the Hammer block safety in the hammer, but later ones dispensed with this in favor of the Pietta overlong cylinder pin. Uberti makes a replacement hammer for those who wish to eliminate this feature on the early guns, and most have been replaced. Piettas have always had the correct hammer. The Piettas are a little closer in dimension as well, mostly in that the Ubertis have a slightly overlarge cylinder, but this is meaningless on the line.
Both currently come with the overlong cylinder pin safety, along with the thumbscrew cylinder pin. But you will find a standard retaining screw in the box, and the first thing I do is swap out the long pin for a standard length Colt pin.
Now. If you're talking about one of the several "Cavalry" models made by Uberti for their own brand as well as various other importers, then there is a difference: the Caliber markings. On virtualy all saa repros other than the 7th, the caliber is stamped on the barrel as "45 Colt". On the 7th, as on the original military SAAs, the caliber is instead marked on the side of the triggerguard, as a simple "45". There are some other differences, but that is the most significant to those looking for a Military marked repro SAA.