Sure, whatever flows your boat, I have been using Riot Shotgun for a while and used Lucky for most of the game. And frankly This Machine is almost balance against lever-action except for the ridiculous high spread in comparison (and unrealistic).
And yesh, since VATS is main cause of death, I only use it for cinematic effect.
About the spread on This Machine... as a boy, I had an obsession with the Garand, and geeked out a little too much on Garand websites and forums. These guns can get nasty amounts of throat and muzzle wear over the years, due to the continuous usage in mediocre conditions and as training weapons by inexperienced kids bitter about the possibility of being shipped off to Vietnam. I know, Fallout isn't real life, but these guns do accumulate a good amount of wear and tear. I'm guessing the muzzle of This Machine would gauge around 4-5, which is considered barely acceptable. Semi-autos are usually marginally less accurate than bolt-actions, as they are optimized for reliability and cycle speed, not accuracy. Having that operating rod flying around doesn't help anything, just ask the National Match armorers! Besides, it'd be of dubious use for really long-range engagements, as it lacks a scope mod. Just my 2 cents.