Floyd
Depending on the weight of the M26 plus the weight of the rail it is mounted to, this could wind up being the most front heavy weapon you could imagine.
I'm a bit peeved by how heavy the quad rail and accessory grips on my Ruger SR-556 are by themselves. Granted they do help to keep the muzzle flip suppressed a bit.
I think I'd rather have a squad specialist carrying a Saiga, Remington 870 or other dedicated "Avon Field Representative" for opening doors. Avon calling! Boom!
Speaking of the 870, with an 18" barrel and a synthetic stock, it is a very light shotgun to carry. I love mine!
Having a match HBAR on my AR that's three pounds heavier than a standard AR barrel, I can tell you that while front-heavy is uncomfortable, it's not impossible to use. Though I can see how a soldier carrying a Serbu and a handful of shells on a drop-leg platform would be just as effective as someone with a masterkey underslung.