You should choose IIM Kozhikode. SJMSOM is a good B-School and maintained a decent record over the last few years. However, choosing IIM Kozhikode will offer you the brand value advantages of IIM and long-term returns.
IIM Kozhikode has a better faculty base for management. You will also get good opportunities to attend lectures by some of the famous visiting faculty.
IIM Kozhikode placements are pretty good as well. As per the 2022 placement highlights, the median CTC offered to the students is around INR 26.5 LPA.
My brother is an alumnus at IIM Kozhikode. A few years back, he was in the same dilemma that you are right now. Keeping in mind the brand value and the long-term return, he opted for it.
Additionally, IIM K has the most beautiful campus among all the IIMs.