How was the scan on your 811s like?
Actually, I take it back. They were pretty horrible. At least compared to the scans of the other folks listed in this thread! (PI > 800, PO > 100, though maybe it was my scan settings? I don't know, didn't save them). Luckily I have 2 Pioneer DVD players that will play anything. I don't think my scans are necessarily reflective of the quality of the discs (no pun intended).
I did a surface scan, which showed no bad sectors. I also do a quick test using DVD Shrink to see if my discs will play under "real world" conditions- I just analyze the DVD I just made, and if it gets all the way through, it should work in my players. With this burner (Liteon 811s), I've given up the quest for pretty scans. 'Tho maybe it's time for a Benq 1620 for some "peace of mind" .