Burned some home video onto a verbatim 16x +r dvd on both my Benq 1620 (dell 8631) using C21 firmware, and to my Plextor px-716a using 1.04 firmware.
Burned both with Sony DVD Architect at 16x with bitsetting to -rom.
BENQ SUM8 Test: AVG PIF: .04 MAX PIF: 9
BENQ SUM1 Test: AVG PIF: .00 MAX PIF: 3
Plex SUM8 Test: AVG PIF: .06 MAX PIF: 9
Plex SUM1 Test: AVG PIF: .00 MAX PIF: 3
As you can see, with this particular media, there is virtually no difference in the burn quality between the Benq 1620 and the Plextor 716. The Benq was a few seconds faster on the burn, but both had excellent burn results on this media.