One of the biggest thing that I noticed early on with the Super Blackhawk Bisley hunter, was it's ability to hold same POI with the super heavyweights and the standard bullets. I'm talking 340-350 grain to 240-250 grain. I found a load right off the bat with the 340 grain I had made to my spec's by Mountain Molds.
But when I started working up a load with the 250 grain I designed at Mountain molds with the same nose dimensions, I started noticing my POI was not changing. I even loaded some of the 255 SWC bullets I had from an old Lyman mold and got the same results. It did not mater if it was the starting charge or the "very" Ruger Only loads that this revolver seems to prefer. Everything I was loading was plenty close enough for 50 yard hunting for game as small as Ground Hogs to as big as Moose. These Targets below were shot back to back, and after seeing them was when the scope was moved foreward in the ring's, and both sights and scoped zeroed. Open sight or scope in place both loads shoot together. I believe the heavy rib on the barrel is what keeps the POI so steady because of controlling barrel rise? But out past 50 yards is where the big 340 shines!
The scope as you mentioned was why I bought this gun. As my eyes changed, I needed something for those first and last legal hunting hours. I was hoping the Ruger would hold it's zero removing and replacing the scope, as I wanted to still use the open sights when I had full daylight to see them, as I did some pre purchase investigating and found a couple scopes that would fit between the open sights. It has worked great. Allowing me to hunt the first hour or so if predawn to good light where I can again see my sights well enough to hunt with, I remove the scope till I am again getting into the last light of the day, when I replace the scope from my pack and hunt them last few hours of legal light with the optics knowing I have my zero for out to 70 yards or so in the lower light, and it only takes a hey or quarter from my pocket to unscrew and re tighten it. This is why I say I wouldn't consider less than $1500.00, and that would probably go up I ever thought someone would be willing to give that for one of these fine limited run of revolvers.
These were the seasons I hang on to this revolver, and the older these old eyes get the more valuable this becomes. I could have, and did scope my 7.5" FA in 454, but many times I wished I could remove it and use the open sights. Once I bought this revolver, I sold both my FA's one 6" with both cylinders and open sights, and the 7.5" scoped, hunting in the eastern US I just did not have a need for the hotter 454 loads. the 7.5" I don't miss, the 6" was one of my biggest regrets selling any gun I ever owned!