I think the oneI have is the Mod 22 in .45ACP and it is all I need. Very accurate and handles ball ammo and HP's easily.
A pal has the .45 Colt and shoots with me and uses .45ACP rounds as well. I use moon clips and never noticed what he does to use the ACP rounds but his will surely shoot them well.
If I were going to Alaska where a handgun would mean safety, food etc. I think I would opt for the .45 Colt revolver.