For thin watches, I believe the Miyota 9015/9039 is a better choice, since the Sellita is 4.60 mm versus 3.90 mm for the Miyota. The SW200-1 gives watch manufacturers the Swiss Made ecosystem and the associated consumer perception. A Seiko NH35 is practically the Toyota Hilux of mechanical movements. It's cheap, enormously widespread, easy to replace, and extremely well understood, but still not "special". The Seagull offers very similar functionality to the SW200-1 at a dramatically lower movement cost. I also think watch buyers are becoming much more movement-conscious. Ten years ago, people were mostly happy with any automatic movement. Now people ask: Which automatic movement? And that's changing what brands advertise.