We consider a user-centric cooperative-cellular network where ${K}$ base stations cooperate to detect the signal from a mobile user in the presence of infinitely many interfering mobiles, using a linear Minimum-Mean-Square-Error (MMSE) receiver. As the number of antennas per base station grows large, it is shown that the uplink spectral efficiency approaches an asymptote that has a simple form, which reveals the relationships between key system parameters. This result generalizes our recently reported findings, which were applicable to mobiles distributed as a Poisson Point Process (PPP), to any model for mobile locations as long as the mobile density exists.