Always seemed a smartly setup service, from a distance, the Mexican Navy.

They arent going to be facing down Kirov class battlecruisers, squadrons of strikefighters or dozens of advanced SSN’s so they havent equipped themselves to meet those threats.

They do need to keep positive control over their EEZ and counter narcotics infiltration in partnership with their big neighbour. So they buy the design to an economical, if basic, Spanish OPV and develop it into a series of, apparently, competent and efficient OPV classes. They in mounting the Bofors 57 with 3P ammunition are more adequately defended, against even quite sophisticated threats, than most other vessels of this type and, sensibly, have fair provision for aviation deployment.

Rumours suggest that they want to develop a circa 130m GP frigate with greater range and warfighting capability, presumably this is to allow them to dispense with the Knoxes and carry their patrol and surveillance mission farther out. Makes sense if they can afford it!