I was wondering how many of you guys use reference tracks to mix to. And if you do, are they mastered tracks?? I know I've always had a couple tracks I turn to when I'm doing mixes, but I actually go the my mastering engineer's website that I submitting the tracks to, and listen to his or her "before and after" samples to see if my mixes are comparable to the others and to see how the mastering will affect it. Just something I've never really discussed with other engineers. What's your guys' input?