Tikkanut, you've hit on the best reason to own such as carbine, ammo interchangeability. I'm considering one as well, but in the .44 magnum lever action flavor.

If someone made a realizable .44 Mag upper I'd sure consider it, but the rimmed cases don't seem to like magazines very well.

You didn't use logic or reason to get into this opinion, I cannot use logic or reason to get you out of it.

You cannot over estimate the unimportance of nearly everything. John Maxwell