My vote would be a 10" Super or a bisley hunter in 45 colt or as already mentioned, a standard bisley with a good scope mount. That will be easier to find than the hunter in 45 most likely. The standard colt will do most chores you would have it do. The 454 is very nice in a FA, I've never fooled with the BFR but I've seen folks have great accuracy from them. I wouldn't worry too much on BC and wind drift of the big slugs at 100 yards. I don't think you'd be able to tell the difference in the real world honestly. In the 10" Super, I've never had one that didn't shoot the RCBS 300SWCGC bullet incredibly well. In the 45, there are tons of choices in the weights you want to use. You really can't go wrong with any of your choices.