Hook - I owned one of the Ruger .44 Mag carbines in the early 1970s. Kept it less than a year and sold it since it didn't seem to have a whole lot more oomph than my Blackhawk 7 1/2" in .45LC. I can't recall any feeding problems - it's just that I expected some kind of major improvement in "thump" and didn't get it. And it didn't have the smooth action and sex appeal of an M1 carbine, which may not sound logical. At least that's as best I can remember.
Today do I wish I still had that Ruger? Somewhat, but not enough to buy one again unless it was a steal. I can't remember any gun I parted with that I am still glad is gone, except a post-'64 .30-30 Model 94. Had no need for it and back then we still worshipped the pre-'64 guns.