At 2.5 billion per mile, SAS perhaps is one of the worst investments in the infrastructure and by far the most expensive subway line in the world. Why would anyone spend so much in a borough that already has like 20 other subway lines is a mystery. It obviously made the lives of some people more convenient but at this cost I doubt that this convenience is worth it. There are so many other transit projects which would make way more difference to people's lives. SAS is a total waste, in my opinion. That money could have been spent in other boroughs of NYC. If everyone hates SI so much, it could have been Queens.