I've got on chambered in 416 WBY, shoots great. We're going out to shoot a new 338WM of my cousins today too, it's a newer MKII. I owned 2 of them 338WM's also, both Rugers, they shot great with 4350 and 250gr X bullets, that's all I shot in it. My other buddy Russell, his 338WM shoots fantastic, 1/2 - 3/4 with 225gr Remington CoreLoct factory ammo!
You're right, there isn't a ton of people around here posting about there Rugers, but don't take that as meaning they don't shoot, just ain't so... I've seen many more shooters from them, than not! My buddy Brian, him and his son Josh both shoot Ruger 338WM's, and they'll do under an inch with 250gr X bullets! I think Josh is 11 years old, but he's been shooting that 338WM for two or three years now. He got his moose again this year, about 200 yards in the swamp. This kid whips *** on most all my friends shooting trap with a 12 too!
Most all my experiences with the Ruger have been with the 338WM, as you can see.