Gazelle? Does anyone know anything about them?

1. Clamp: the one with the "arrow" (and Gazelle logo) is quite okay. Haven't seen a single one that failed.
   The one on the picture (Marktplaats) is the 1st version, with a smooth transition from braze-on block to tube. That's a weak spot. A crack (?) will appear on the transition in many cases. Sometimes, one half of the black may fall off completely.
   
   
   

Okay, I only now notice this one is not with the arrow clamp. I do have a friend with a Champion Mondial with a clamp alike the Marktplaats one and it has failed. Bummer of the nice frame. Did it ever became clear why they failed with this construction?