Bullseye in San Rafael certainly does, and I believe Marin Firearms in Novato also does.... in case you're like me and working daily in Marin while living in SoCo.
Since I gave up my peace officer status a while back I presumptively don't have an HSC exemption, but I am hoping that my 30 year old 832 PC training certificate will exempt me for future handgun DROS. I don't much like the idea of paying the state $25 every few years for something that they could (conceivably) take away.
But that's just how I feel about it.
What I wish would happen is that they would put a hunter safety course / possession of a hunting license in as an exemption. One has to prove taking hunter safety to get a hunting license, and firearm safety is taught in the hunter safety course.
"A gun is as good or as bad as the man using it. Remember that. "