From the reviews I read there didn't seem to be a whole lot of change to the movement other than the certification name / process. The 8500 would be extremely accurate and serve anyone well but they're pushing Master Co-Axial's now.
Titanium is a nice material for a sports watch, especially if you swim or shower in it regularly. It seems more forgiving of smudges etc if you're an OCD obsessed WIS like me.
Haven't actually owned the Planet Ocean in Titanium but I'm sure somebody here does or has and will be more helpful
