I've got three Ubertis: a one year old Dragoon, a five year old Cattleman and a 30 year old 1860. I've got three Piettas: an 1862 Sheriff, an 1860, and an 1858. They're all two or three years old.
The Uberti Dragoon is really the peach of the bunch, but the 1862 Sheriff is awfully close. I think that the difference, to me, is the roll marks. I've had timing problems with the Uberti 1860 and with the 1858, both of which were easily fixed.
I've had problems with the screw that locks the arbor on the Cattleman coming loose, but I'm not sure whether to blame Uberti or Samuel Colt.
Every now and then I stop by Cabelas and look at the Piettas that are sitting around there. It seems to me that the fit and finish of the guns in the case are better than the 1860 and 1858 that I own, so I agree with the contention that Pietta's manufacturing processes are getting better. And even if Uberti has a slight edge in appearance (which does count), the Pietta's are definitely a great value because of the price. I suppose that if your goal is a defarbed gun for reenactment (or just because you can't stand the lack of authenticity), the Ubertis may be a better starting point.
Either way, I'm glad that we've got the choice!
Well we don't rent pigs and I figure it's better to say it right out front because a man that does like to rent pigs is... he's hard to stop - Gus McCrae