I would also vote for Wurth Wood Group if you can get there. Even though they don't have a showroom you get to see the plywood when they bring it out to load it. I have asked them to bring out the whole stack before when I was buying cherry or walnut ply. It's usually very good but if you see something you don't like send it back, they are aware of how much you are paying and don't have a problem with that.
Also, Hicksville Planing Mill in Clearspring, MD does sell plywood along with a selection of hardwoods to drool over. Their prices are always reasonable.
-Alden