I have a colvin pinky schooner that has Goiot (french) hatches and ports.
They were bought out by plastimo recently. We are very pleased. They are
cast aluminum. Hard to beat bronze and stainless if one wishes to have
something that can stand years of neglect and ask for more. However the
cost and the weight of bronze / aluminum are rather high. Of course there
are electrolsis issues with bronze and to a lesser extent with stainless.
I have a challege keeping paint intact in the vacinity of stainless bolts
that the builder usedto secure life line post bases to the bulwarks.

Best
George