My 455 Canadian shoots almost everything super accurately; point of impact moves up or down depending on the type of ammo.
Only one I would stay away from is Federal; a half dozen guys at our club found it not only terrible for accuracy, but frequently had split cases. So did I. No other ammo did this.
The 455 is as good as any and better than most IMO.
It really is batch related. Winchester is very very bad for split necks. Have to use a knife to extract.
I have shot 1000 + Federal and none split. I do have a never fired Hornady vmax that is split. Go figure.