I bought a carton of chocolate milk a week ago, and although it was soy milk, it tasted just as good as dairy milk. It's made by the Silk brand. I didn't even know that they made chocolate soy milk, and I didn't know it would taste that good.
I've bought the regular Silk milk in the past, but the only other flavor besides the regular one I've ever bought was the Vanilla one. All of their flavors seem to be of good quality.