Galvanized is cheaper, stronger, longer-lived if maintained properly, but not very attractive, nor compatible with current available fittings. BTW, to my surprise, Paul Kruse told me that galvanized Dyform is available, and is used in some industrial applications. On Fossett's various boats they usually replace the rod before any significant ocean crossing. Between full replacements, Ben cuts off the bottom rod ends and reheads them - says he has never seen a rod failure anywhere else but at the head. The diamonds are rod, but the uppers and runners are Aramid with a black plastic cover, terminated in what looks very similar to a giant size Norseperson.
Every wire is instrumented.
Gino seems to feel that is as good as SS now that the terminations have gotten past their teething problems.