The bearings do wear out, although I haven't actually worn mine out, yet. I've got a lot of miles on my first one, too, probably 30,000+.
I've known of several people who got their Edelux lights waterlogged and ruined. They're mostly okay in the rain, but not a guarantee! That's obviously not a generator hub issue, but if you wind up sitting in the dark, it doesn't much matter where the weak point was, either.
On one of my bikes, I had to remove the front wheel to haul it, and eventually, the little wiring clips were getting loose, but minor issue.