You cannot call Sadak a remake of Taxi Driver, but it is definitely inspired by it. The theme of a TaxiDriver befriending a prostitutew and saving her was definitely lifted off from Taxi Driver. But the love story elemnts and a great role by Sadshiv Amrapurkar, really makes it different. But still Mahesh Bhatt should have acknowledged that he is partly inspired by Scorcese's masterpiece
you got to be kidding.. there is absolutely no similarity between the two films.. though some action sequences were taken from Scarface.. but taxi driver.. absolute no no !!