Quoted:
The weight loss doesn't seems very substantial considering all the changes.

Quoted:
Having lived through those days as a consumer with cash to spend, a lot of it has to do with price.  Back in the 80s you could get a Colt's AR-15 for ~$450 or so and a Mini-14 for a bit less, it was hard to justify spending ~$800+ for the others.  I bought an HK-91 for about $800 in 1987 and sold it shortly after when I realized that the accessories were stupid expensive.  Magazines were ~$30-50 each, the freaking cleaning kit (which now sells for about $5 surplus) was $25 new.  Then you have the fact that other than HK, none of the other brands really advertised and were more boutique guns than anything.  We look at those prices today and shrug, but consider that in 1987, that $800 HK-91A2 would cost ~$1670 in current dollars, and a $30 magazine would be ~$63.

In the end, the selection was pretty exotic, and the stuff was available, but it became a simple issue of cost, lack of the manufacturers' advertising and educating the public, and the mindset that "those guns" were the purview of survivalists and wannabes.

If you can find it, in 1982 Guns and Ammo released a publication called "Assault Rifles: The New Breed of Sporting Arm".  I found a copy on eBay:

Guns and Ammo's Assult Rifles: The New Breed of Sporting Arm"

Quoted:
The M1 extended rail would be a great choice if you plan on using a non-steyr optic.

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