The .280 AI and 7mm WSM are neck and neck just behind the 7mm Rem Mag with comparable bullets.
There's a couple of good threads here if you do a little searching specifically detailing out kills on Moose, Elk, Both species of Bear etc so the performance is certainly there.
I was just eyeballing an awfully nice stainless M 70 in 30wsm (again just a hair lower on performance than the 300wm) over on Gunbroker. It'll probably sell under 800.00.
The WSM's certainly have their place and the application you are talking about just screams for either the 7mm wsm or .264wsm (same case just necked down to 6.5).
I don't own one yet but I keep leaning towards the 325wsm in the Model 70 coyote light model.
They are not "light" in that they are not a mountain rifle weight, but they are lighter than the Sendero by a couple of pounds if I remember right. The taper on the muzzle is similar to a light varmint contour. I read somewhere on Winchester's site that the taper is similar to that of the Sendero but finishes around .750 at the muzzle end instead of .830.