I've found the .454 Casull SRH to be the best 150yd hunting pistol I've ever come across, in over 35 years.
(Including an 8 3/8" M29-3 w/issue scope rings, a .45-70 T/C Contender Super 14 Hunter w/issue T/C scope, and another T/C Contender in .375 Win.)
The .45 Colt loads make a nice mild/target sub-load, the Winchester 250gr JSP's make a nice mid-range deer/blackbear load, and the heavy loads for anything heavier.
My SRH is an early, 7 1/2" barreled one - completely as issued, with the addition of a small reddot sight.
I wouldn't waste the engineering, my money, or carry the weight, if the same gun were in a lesser caliber, like .357, .41 Mag, or .44 Mag.
IMHO, the Standard Redhawk is much better suited for those cartridges.