Magazines with a continuous curve allow for a much more robust, impossible to tilt follower.
New, clean USGI mags work great. I'll wager that continous curve AK mags will fuction far
better with debris in them, due to the follower design.
older USGI magazine followers nosedived ocassionally, until green followers were designed to try and fix the problem.
I believe HK has yet another follower design, and I brought some tan colored ones from Magpul
several years ago, pictured below, which are a recent attempt to improve on the green follower.
Note in the 3rd picture below, the kind of follower that can be used in a continuous curve magazine.
No frigging way you can push the front forward and not have the entire follower move in
perfect alignment.
This makes for very robust feeding.
Also included a pic of an M-14 20 round mag follower in this pic.
In summation- my main beef is with the crooked design of the USGI mag, in order to accomodate
the longer magwell of the AR. This design will not accomodate a follower as reliable as a
continuous curve magazine can.