What SC Said

I like scopes on guns that I will have time to view the target and find the target in the scope. For quick pull up and shoot shots a will take open sights every time. I limit my shots with the open sights to 50 yards or so. With a scope and a rest I will shoot my wheel guns out to about 100 yards. I killed my first pig with an open sight S&W 4" Model 29. I have since shot them with both scoped and open sight guns. The scoped route seems a bit easier for me but you need--time to aim--. With the open sight gun and a lot of range time you can do very well.

As for the 454 I would use a loaded down 250 XTP it is still very strong and will help with recoil and second shot placement if required.