I have eaten squirrel, tastes a lot like dark meat on a turkey. There isn't a whole lot of meat on one, the meat is ULTRA lean. If you're shooting them just aim for the shoulder and that will down them in 1 shot and have no effect on the meat. I usually use a .22LR subsonic round to limit them blowing up into pieces.
Where I'm at I've got only reds, not a single grey/black to be seen, and I live in 60 acres of mixed hardwood and cedar bog, then 5 minutes from here my parents have greys and blacks all over the place.
I shoot anything that gets into the bird feeders and throws the seed out onto the ground. I don't mind the rats feeding on the ground, but when you climb the pole bad things happen.