{{Hebiquote
|quotetext=The RO635 is not merely a submachine gun-sized AR-15 carbine, like the [[Mark 18]]; it is an actual, literal submachine gun. It is not considered to be part of the AR-15 family of rifles, because it uses a simpler blowback operation instead of the direct impingement gas operation system that is traditionally found in AR-15s. Despite that, the RO635 uses the exact same ergonomics as its more powerful cousins, and is viable as both a training platform for other AR-15 rifles and as a legitimate workhorse submachine gun.
|quoteauthor=Tempest
}}