Here's what I do know:
1) Whether or not they have idencial chips does not necessarily affect whether you can flash one to the other.
2) You don't appear to have any of these drives in your possession, and seem to have some personal stake in seeing that only the Benq drive can be flashed to DL. (which is still also open to debate)
3) NicW may have some supposedly DL rated drive in his posession, but he has not offered any evidence as to what model it is. I know of two possible models it could be, only one of which will be "compatable" with an 812.
4) Since DL burning strategy specs have not even yet been established, NO drive is currently burning DL in spec, and will not be for at least a couple months.
5) An 812 CAN be flashed to an 832, (DL), but whether it actually works or not remains to be seen, since nobody knows how they're supposed to work in the first place. And media is not available for the most part.
6) You need to check your facts before mouthing off, and you need to stop making the same posts at every forum on the planet.