Yes, it uses the speed set in verify mode; I just checked that and it worked. However, the verifying speed started from 1x upto 4x. I had set for 4x, and I was expecting that the verify speed would be constant. But that was not the case. Log said effective read speed 1x-4x. Is this drive/firmware issue/strategy?
About the quiet setting, I don't know how to enable or disable. It's probably automatic and possibly has to do when you playback B-R video discs.
As for the speed limitation, I use BDs for cold storage backup. I want to make quality backups, that's why I choose verbatim hard-coat HTL M-A-B-L disks (that are rated at 6x) and burn them at x4 (somewhere I read that even burning too low can be bad for disks). Also, when verifying at max speed the drive is about to melt from the heat, and also makes a lot of noise (not alone in the house, burning disks late at night).