Coastline or riverbank?

Here are 2 different approaches used one near another:

  1. I just added more points to detalize the coastline (natural=coastline)
  2. yohanson drew a similar thing as another polygon, with waterway=riverbank

(here are both one near another)

Which way is better?

If it’s a riverbank, then use waterway=riverbank. If it’s just an inlet in the coastline, then use natural=coastline.

Ok, thanks.