Need a little advice on digital cables for my DVD player. It has outputs for digital coax and optical. I've read that optical cables that have really good fiber optics can be expensive. I don't mind paying the price if the benefits are realized. Is there really a big difference in the wide range of prices with the optical cables? I saw a RCA for $20 and others up to $70 /$80. I don't know if optical is better than coax digital. I would appreciate opinions on both optical and coax. Bud S.