Job and career prospects are relative terms, which depend a lot on any individual. Both IIMs and FMS is reputed college for MBA but FMS is comparable to top IIMs, the new IIMs are not that par with the FMS. The placement of FMS is quite high and matches that of BLACKI( Top 6 IIMs). If I compare top IIMs with FMS, I would say IIMs have a better name than FMS, so growing up the ladder in your career is more when you pass from a top IIM. As the alumni base of an IIM is more than that of an FMS. So according to me 5 years down the line, a top IIM guy will be in a better position.