Thank you for the link. Great ressource.
I agree, in India the bulbul tarang has still maintained the characteristics of the japanese original model : a typewriter with poor sound. However, in Balouchistan since it arrived 70 years ago the instrument has changed so much as regards esthetic but mostly building and sound that it has taken its place among the traditional instruments like sorud and ghaychak. Yesterday for No rouz, the persian new year, i watched a tv program showing traditional songs and music from all parts ot Iran and there was a balouch benjo in the middle. That's incredible such a new instrument has reached similar status into this traditional and renowned conservative culture !
I put a video of Mohamad Delnavaz a iranian master of benju. He is permanently working with builders to improve the instrument.