Ok, there seems to be some confusion about Stoner Rifles. There are basically two kinds.
The M-96 is based upon the Stoner machine gun developed by Eugene Stoner back during the 1960's. It was the original modular weapons system, with a carbine, rifle, lmg, and bren style gun base on the same parts and operation. Stoner had previously designed the M-16, which the military had already adopted. Some special forces groups where armed with the Stoner during Vietnam. The military stayed with the M-16. The guns made by Robinson appear to be a modern version of the original. They are made by a different company than the SR 25.
The SR 25, as built by Reed Knight, is a compleatly different gun. When Stoner designed the Ar-15, he originally started out with a .308 version known as the AR-10. The basic design was scaled down to .223 and became what we know know as the AR-15. The AR-10 was only adopted by a few small countries and then faded away. The SR 25 is a resurected AR-10.
I have handled the m-96, but have never used one, or known of anybody who has one. No opinion of whether it is worth it or not.