A few points
Colt 1st Dragoons have oval cylinder notches too.
Second generation Colts use a cylinder, barrel, and backstrap sourced from Uberti. Other parts were made by Colt. The "C" series, 2nd Gen. guns were made in Hartford, at the Colt factory.
"F" series 2nd Gen. Colts were made from the same parts, but production was moved to the old Iver Johnson factory in NJ. The guns were then sent to Colt for final inspection, and marketing.
The Third Gen., or "Signature Series" guns, were made at the Iver Johnson factory, entirely of Uberti parts, under license from Colt. The manufacturer was Colt Blackpowder Arms Co., which was not owned by Colt. It was owned by Lou Imperatto, who was Colt's largest distributor in the US. (all info from an article in Guns and Ammo)
IMO, the Colts are worth the price difference, depending on the model. You can usually get a 2nd or 3rd Gen. Colt for $500 or so. Many of the Italian guns are well over $300 these days. The Colt Walkers (2nd or 3rd Gen.) tend to go for $800 or more, which is a little steep, but they (Colts) are much better made, and they use much better steel for lock parts than the Italian guns. They don't break like the parts in the Italian guns, either.
Just ask Pohill.