So far no free flows with "normal" use - yet. My preferred LDS actually uses these for rental gear!! I've seen a couple free flow when people "test" them on the surface in sub-freezing temp air, then jump in the 36F water. Shut off the valve and wait a few minutes and the problem goes away. I've had my secondary free-flow when I had it "upside down" when I GSed off the boat. OOPS! Hey - at least it's SUPPOSED to do that! Stopped when I flipped it over, though.
I like that they are actually environmentally sealed, so the cold water never touches the guts of the first stage.
I like that they are actually environmentally sealed, so the cold water never touches the guts of the first stage.