Ok I see alot posts about BSKB fw..and of course as always I never test stock fw and jump right and used a patch BSKB with TY02@TY03(as this worked great on my 1620 with TY02)
which fw seems to give best write quality without qsuite2...
I burn all the TY02@TY03 at 12x
My first TY02@ty03 at 33000PIE with slope at the end and PIF total of 79..this was BSKB modded no qsuite 2(same ty02 batch only gave 16000PIE and PIF of 79)...when I used qsuite 2 with wopc off only got same rough PIF 30000 and PIF of 160....third burn was qsuite 2 with wopc on, solid burn on over speed off....same 30000 PIE and 137 PIF with more right at the end of the disc
My small sample seems to show my 1620 is slightly better burner
the 1640 seems to give a slope of PIE at the end(max around 30) with total of 30000 ..PIF look good as total<200 but again increase near end of the disc
so does BSHB, BSJB work better than BSKB when not using qsuite 2...