Oops.. my bad. I'm surprised by those results with the Sony discs. Given, I don't have a GH-20N (yet) but they've worked very well with other LG drives.
The end of the media looks much better than the 20x-burn. But I´m confused about the PIF-cluster at 2GB. I made 2 scans, but forgot to save the 1st one, but I´m sure I don´t had this big cluster at 2GB