Can someone explain what the difference is in the manufacturing of blank DVDs that can make a particular manufacturers DVD un-playble in the vast ocean of DVD players out there? It does not always come down to +/-R. A -R disc from one manufacturer to the other may or may not work in certain DVD players. Seems like the manufacturing of these discs would be an industry standard?

Last question - DVD Duel layer blank discs. Most older model DVD players don't seem to play duel layer/burned discs. Which makes this option unfavorable. I know at the present time there are only DVD DL +R. Is there going to be a DVD DL -R and may they possibly be more favorable in working in some of the older players? I have a Panasonic F85 that is a great player, but won't play anything other than the menus on a DVD DL +R. Am I just SOL with duel layer discs with this player???