No Experience but can help with the Energy numbers. As anything sometime the most energy may not be the optimum, if the barrel is too long for manipulating in close quarters and or one cannot manage recoil. That part of it has to be a determination by the shooter and what conditions. Such as if one knows they will be in the open without being in an ambush area, then a longer barrel may be better. If a Grizzly has already knocked you down and on top of you, the shorter barrels may be the only tool one could possibly manipulate. The following are energy numbers out of the Hornady web-site. They had muzzle energy, 50 yd energy and 100 yd energy. I chose to calculate at the 25yd energy value as a relative value:
9mm Plus x 4"brl. 350#ft
357 Mag x 8"brl. 500#ft
41 Mag x 10"brl. 1000#ft
44 Mag x 7.5"brl. 890#ft
45 Colt x 4,75"brl. 430#ft
454 Casull x 7.5" brl. 1710#ft
460 S&W x 8.38"brl. 1915#ft
480 Ruger x 7.5"brl. 1170#ft
50 Action Expr. x 6"brl. 1250#ft
500 S&W x 8.5" brl. 2617#ft
Best Regards,