First of all , let me make it clear for you that both the exams are different. One is for MBA (CAT) , and other is for M.TECH (GATE). In both the exams it totally depends upon the college and the placement that you will get. For example , If you do MBA from IIM Calcutta , and you choose consulting, if you are recruited by a top consulting firm, then there is a very higher possibility that you will get to travel the world and make a lot of money. Same with M.TECH . So , it totally depends upon the college, placements , and the stream you choose . To sum up, choose that course for which you are passionate.