I was getting data off of an old 2003 disc earlier tonight, and decided to scan it, to see if there is any noticeable deterioration after three years.
I have two copies of the same data, one on a DVD+R, another on a DVD+RW. I've scanned both and the results are below.
Both are Memorex-branded, Ritek-manufactured media.
[The "forest" of PIFs on the DVD+R is due to the way the old Ricoh MP5125A drive burned DVD+R and si not a media deficiency. I suppose Ricoh used ROPC/WOPC before its name was widely publicized by the marketing machine.]
Anyway, I am quite satisfied with the state of both discs after 37 months of storage.