NMIMS Mumbai is a superior BBA/B.Com school than NMIMS Navi Mumbai. It was founded in 1981, long before NMIMS Navi Mumbai, which began in 2017. It has been in education longer and has had more time to build a reputation and establish its curriculum, faculty, and infrastructure.
Second, NMIMS Mumbai has more students and better instructors than Navi Mumbai. The Mumbai campus's more popular BBA and B.Com programs attract more students, and the better faculty ensures quality instruction and guidance.
Thirdly, NMIMS Mumbai is the primary campus while Navi Mumbai is a newer campus operated by NMIMS Mumbai. The Mumbai campus makes key managerial decisions, which will benefit main campus students. Navi Mumbai has less autonomy than the main campus.
Fourth, the Mumbai campus has good placements, and BBA and B.Com students need this to find secure good job opportunities after graduation.
Finally, the Mumbai campus is at Vile Parle, a prime location. This helps students commute and access various resources.