Since the adoption of CNC and CAD processes in the late noughties, Pietta's are VERY different to their earlier, hand-fettled, products. They are, IMO, the equal of any other high-quality Italian-made firearm and I recommend them to anybody. I've never seen a blue Model of 1858, though, but I shot beside my old pal Ken yesterday - me with my ROA and him with his recent Pietta and both were equally well-made to me.I thought I'd heard that Pietta's were mechanically better. My CVA Walker has a short arbor too. I need to fix that.
Just remember that if the version you buy has adjustable sights then it does not comply with the N-SSA rulebook. You might 'fudge' the shiny finish - stainless-v-nickel - but the fancy sights are a no-no from the off.