Some of you might have noticed my enthusiasm for the Hugyfot Hugycheck electronic pressure-testing system for ensuring I don't flood my camera. I've bought a lot of different housings in the past and have a lot of ports for them. It is my opinion that the Sea & Sea optical glass dome port (is it Athena?) gives the sharpest results from side-to-side across the frame.
I can now fit it on my Hugyfot housing thanks to a Sea & Sea to Hugyfot converter now made by Hugyfot. (They make other types too.)
Of course, a side effect is that I don't have to buy a macro port for the Hugyfot either!