Considering the ROI and fees, JBIMS is a better option than IIM Lucknow. Also, it is affiliated with Mumbai University so has a brand name also. But in reality, these factors are short-term and cannot be considered if you are investing in your career.
Overall, IIM Lucknow has an upper hand in almost all aspects. Be it placements, faculty, or brand name. Had I been in your place I would have chosen IIM Lucknow mainly because
Both these aspects are lacking in the case of JBIMS because it is standalone and has a very weak alumni network. It also lacks accommodation facilities.
Overall both colleges have roughly the same worth and choosing one over the other is just a matter of preference.