Ron Ruff wrote:

No personal experience with DA, but others have noted that it needs a
*lot* of maintenance if you ride in wet conditions. Ultegra's last
~10-30K miles it seems... zero maintenance.
A friend of mine has an old 8 speed bike with a Shimano 600 group and never
changed the BB in 100.000 miles. He's a lightweight guy and makes more
rpm's than I do. I think that influences the longevity of a BB in a big
way.

Gr, Derk