I did some tests after x-flashing to EW164B on my internal OEM drive and noted that:
(1) burst went from 22MB to 34MB/s
(2) seekm times decreased by about 5-10%
(3) CPU usage decreased by 10-20% (proportional)
(4) Error rates increased slightly (Particualrly PIF errors went from 5max to 10max).
(5) Jitter seemed to decrease slightly.
The tests were done with TY 002 8x DVD+R's, and checked twice. I can posts screenshots later if anyone's interested.
I would really like to know people's opinion, because I am wondering if crossflashing has any real benefits, or if I should flash back to DW1640 firmware. If the error rates are going up, then I can live with UDMA2 instead of UDMA4.