The only point I can see in this is in regard to dvd-rw 1x writing. Which is working fine! Well I guess if you use princos it would choke on the 1.2x overspeed but hey, that's not really the drives problem.
To reiterate, the 1640 burns at 1.2x for dvd-rw (1x). And ppl say the 1640 can't overspeed