The last compelling CD writing speed increase was 24x. Since then, it has all
been modest incremental improvements in speed that really kick in only for long
source CDs.
On top of that, last week I was at a dinner party and spoke at length with someone
who is intimately involved in CDR blank manufacture and distribution. He told me
that 24x is the absolute fastest speed he recommends to anyone writing CDs
for any important/archival purpose. His quote: "Given the deficiencies of
the burners and the properties of the CD blanks, ALL our tests show that
if you go beyond 24x you risk creating discs with substantial errors. These results
hold across every manufacturer and every brand of blank. " He added that
Plextor and Sanyo manufactured drives do better in their tests than anyone
else's).
If you have a 24x burner you're happy with, I can't see any reason to upgrade
again until you replace it with a DVD-R(+/-/whatever) drive, unless you want
entree into the BSD club.
Kwad