Hello Aspirant,

As per my knowledge the dual specialisation started back in 2000 but not a corporate favorite anymore. In this age of specialisation don't dilute your core skills. Go for the subject which you think you will do well in or more passionate about. Also I would say MBA in Finance is a much better option since the course is no doubt tough but give useful results in the long run. 
HOpe this answers you well. Good Luck.