The .44-40 get's my vote. It's noticeably softer shooting and more accurate, at least in my revolvers, than the .45 Colt. I have a .38-40 that is an enigma. It is less accurate and sharper recoiling than it's weight and .400 throats should allow. It isn't awful, but it ought to be better. Rather than experiment with it, I spend the time with my .44's and .45's. If I could have only one caliber, it'd be a .44-40.