95% on the Maple. The mills up north talk about a 'grey' maple as one that just gumms up the blades. It's usually just Box-Elder(a maple with different leaves), that grows pretty quick for that species. With a very light sealer it stains the same as regular hard maple in my experience.
I have found that the heartwood in those logs is just crap, really flaky and splintered after kilning. Thou everything else under the cambium, usually 2-3" is pretty solid maple.