When I learned to play, I studied many styles as well. I also emulated them, but I also put a spin on it and devised my own style. Your friend obviously has his own style, but I guarantee he studied someone's else's style, flipped it and made it his own. It's always good to have someone to motivate you in your craft and be an influence to you. But don't let that CD be your one and only study method. It's a great idea to study your friend, but do it with the plan of devising your own style in the end.