I haven't had the seafood at the Corning (aka Rolling Hills) Casino buffet but I have tried the other offerings. IMO the buffet there, both breakfast, and dinner, are terrible. The only food offering edible is in the upscale steak restaurant.
Canyonville (aka Seven Feathers) seafood buffet is ok. Not a lot of selection (oysters and snow crab legs). Last time it smelled "fishy" as we entered and we chose to eat elsewhere.
Being from the PNW, I think you will be disappointed in either choice. But the Seven Feathers RV park is outstanding. The same can not be said for Rolling Hills.
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