Improved quality CG3B help please

I have a Liteon 851 upgraded with the superb Codeguys VSOB firmware which now shows as an 832 with Dual Layer Burn. (And it works brilliantly well.) Codeguys now list another upgrade to CG3B which offers increased quality. Can any-one please help me with the following:
a)If I install the CG3B firmware will I retain Dual Layer Burn capability?
b)In view of the fact that the drive is realy an 851 should I install CG3B 451-851.exe or CG3B 812-832.exe?
I use Verbatim Double Layer discs.
Thanks in advance for any answers.

a) Yes.
b) Use the 451S/851S version.

My limited understanding, is that there shouldn’t be anything to stop DL capability (unless they had to steal the space from it).

If your drive started as a 451 or 851, then that’s the version you use, since the 832 version for it is a hack, rather than a simple crossflash enable.

All done. Many thanks.