I read that thread but it really isn’t very informative. Where they reliable? Apparently S&W agreed with Stoner that the Forward Assist was not necessary. The link talks about the quality of thE barrel.
Any ideas on how many where manufactured? Was it customer demand for a gun that looked more closely like the ones used by the military that caused S&W to discontinue it and market the Sport 2?
Have I just not looked hard enough to find one for sale? I have built several AR’s so building one with a smooth upper and 1-8 barrel isn’t difficult (well other than the panic is making finding the parts difficult).
The Sport 2 actually seems to be a step backwards to produce a lower quality gun that satisfies the market.
You didn't ask about reliability, you asked about the history. They were poo poo'ed in the beginning as being a "budget gun" that "cut corners". The barrel wasn't 4150 CMV and it wasn't chrome lined. The BCG was not a full auto type. The bolt was not individually HPT and MPI tested, they were thought to be batch tested. The lower receiver extension (buffer tube) was of mil-spec dimensions, but possibly not of the same type of aluminum. They didn't have the forward assist or the ejection port cover. And finally, the hand guards were not lined. All of these things were said to be cutting corners to meet a price point.
Despite all of these "short comings", those of us who purchased a Sport back in the day found that we bought a simple, reliable, and accurate semi auto carbine that made a fine HD, hunting, and recreational shooting firearm. Even some small police forces without a large budget used them for patrol rifles.
As time went on, S&W made changes to the original Sport, as covered in the other thread, with the biggest change being the move from the 1:8 twist to the 1:9 twist barrel.
Once Ruger came out with the AR-556, which was considered to be a "full featured" budget rifle, S&W moved to the Sport II and included the forward assist and the ejection port cover. I believe the quality is the same, but I am happier with the 1:8 twist from the older Sport rifles.