I had no trouble flying out of SFO with my reg, BC and camera housing a few weeks ago. They scanned my bag, hand searched it, then scanned it twice more to get all of the angles.
They did question my Leatherman pliers. I had removed the blades, but OK'd it upon hand inspection. But I got a lot of hassle coming back from Maui with the Leatherman. There were no blades, but the handles could be configured so that the tool was over 7" long, which is against the rules. I won't bring it again. I'll get some smaller pliers.
It seems that the TSAs at SFO see a lot of scuba equipment go thru -- they're used to it and recognize it. Over the past few years I've gotten more questions flying out of Maui and Kona, than from SFO. Go figure...