Just looks like a way to trade reliability for concenience.
Reloading magazines was more frequent in my unit than many in peace time and it always seemed a chore, mainly because of all the whinning like little girlie-girls. Because of our mission we shot ball ammo alot and cycled "ready ammo" It was frequently a work detail sort of a thing overseen by a junior NCO or Acting Jack (ain't got the stipes or the pay but doing the job) that understood that if one of the gus messed up a magazine it might end up in his pouch next time he needed a reload. I would have preferred geing handed my own bandoleers and loading my own magazines, but I did not make the rules. I had the detail at one point and had a couple of "Newbees" though we as often called them somthing less polite and a guy serving Article 15 "extra duty" and someone that had just caught the Plattoon Sargent's eye.
One of the newbees whinned that he had seen someone slice up their fingers in Basic using stripperclips and the other nodded vigerously.
"Look at me. Look at the old boys. Where are your gloves?"
We also sometimes had to do showdowns to prove our magazines were loaded and then it was necesarry to unload a mag and count the ammunition while reloading it a single round at a time. THe occassional pinch as a round got pushed in was a bother and once in a great while someone would git a boo-boo like a small cut or blood blister usually while not paying attention to what they were doing. THe thing I did not like about showdowns was one on occassion found that ammo that was traded between multiple folks over a few weeks some times turned into sections of ball point pins, chunks pencils or a wooden stick as folks built up their own little cache of ammo. Some times simply two round or four were missing so the visual inspection of which side the top round was on would not reveal if an odd number were removed.
I personally thought that folks that did the ammo stealing should have been flogged and ..... let's not go there.
No doubt this new magazine would have made it easier to check for theives and vandals (idiots! that mag might be in their rifle when they need it!) but I wonder if it would even be as reliable as dumb trust. BTW I got made fun of more than once for pulling every mag issued to me and reloading it, but it kept ball point pen barrels out of my rifle chamber.
I have to agree this convertable top magazine looks like an answer to an un asked question, except.....
It likely looks very good to folk that would rather pay $40 for the ability to not load magazines in a more traditional way or who just like gimmics. Those people will pay the prices and makers while make the profits and that is what the market is about.
Around 1983 or so some one was making a plastic magazine that consisted of a two piece magazine body and one piece telescoped into the other. the supposed idea was that Joe Survivalist or Joe Security Guy that stored magazines loaded could do so with out the magazine springs being under full tension. When the lower section was extended it was very easy to load the magazine with single rounds, they were also advertised qas being usable as like 45 round magazines with the lower section exteneded (Oh boy an intentionally weak mag spring with 50 percent more ammo piled on it.)
I don't see them around any more and the last time I recall seeing one it had been epoxied "shut" for use as a normal magazine.
I think Ram-line mad a clear/translucent 3 in 1 magazine that would work in all guns taking standard M-16 mags, Mini-14s, and the old style AR-180 (Guess they could be used in the AR-180B because of that first) I dashed out a bought a couple and found out they did that by building a magazine that did not realy fit any of those rifles. It was either two tight or too sloppy in every one of them. I will say that they did work for a while and they recently worked in a Mini Ranch Rifle. hey did bad things in an AR-180 and AR015 though. The application to this discussion though was that one could simpy see the loaded rounds through the magazine and the mag body even had indicator marks to show the number of rounds. I seem to recall they have twistied wire "constant tension" type springs which are weak sisters and did not always have the umph to look bolts back, but were easy on the fingers to load.
The new magazines are an AR accessory and as we all know, whether it makes sence or even offers any advantages if you build it they will buy it.
-Bob Hollingsworth