I have a Sinn 356 Flieger II that's been barely short of a nightmare to own.
Pusher buttons falling off, stripped crown tube.
The problem with Sinn is getting repairs performed, as they're in Germany, and getting them to ship you parts is impossible. Finally wound up putting an Omega crown on it.
Luckily I have other watches.
It's really too bad, because they do make great watches, until something goes awry.
BMW r1100s, 1976 BMW r75/6, Yamaha xj600s
St. Louis Cardinals
2006 WS Champions
2011 WS Champions