Well, the Mossbergs have a reputation from the git go to shoot very well with no tweaking. Ruger's are nice solid rifles, but I've never heard of them shooting like the Mossbergs without a trigger job (which helps the shooter, not the rifle) and some barrel bedding work, whether it was free floating the barrel on one gun or putting a little tip pressure on the barrel of another.
One of the editors of Shooting Times and Petersons Hunting, Greg Rodriguez, took a synthetic 4x4 in .338 on a brown bear hunt. He's an outfitter, writer, trainer, and while maybe not rich, he's comfortable in life, if you know what I mean. He's got several rifles that cost thousands of dollars each that he could have taken, besides the fact that as a writer, he could have gotten a loaner from just about any company for the free publicity. I find the fact that he took a plain jane rifle that any of us could afford on a multi-thousand $$ hunt of a lifetime, and felt fine using it on dangerous game pretty impressive.
Ruger rifle accuracy improved a hundred fold when they started making their own barrels. When the barrels were outsourced, one would be great, the next would suck big time. The Mossbergs are barreled by ER Shaw, so you know they are pretty good.
But I digress.....to each their own.
