If you need or want a .454, fine and dandy. If you want a true .45 Colt 83, that cylinder will be an optional extra, as the base gun will be a .454, not vice-versa. If you want to shoot .45 Colt strength loads in the .454 cylinder, that's fine too, but you should use ,454 brass to accomplish that, and the internal volume of that case is larger than necessary for those .45 Colt ballistics.
If what you really want is a.45 Colt, there is a significant weight difference in the hand, and on the belt, between an 83 and a 97. It seems to me that the most important question is which cartridge and power level you want, before settling on the model.