Cheap to operate? How can they be cheap to operate when they have 160-180 crew on board?
Compare that to the cheap french Floreals with a crew of 88. They have long range, a medium gun for firing warning shots and a helicopter for chasing down drug runners and pirates. What more do you need? They also have double the range of a perry.
They don't have
Sonar (Perry has SQS-56, SQR-19 Towed Array),
ASW armament (Perry has two
triple Mark 32 Anti-submarine warfare torpedo tubes with
Mark 46 or
Mark 50 anti-submarine warfare torpedoes), a
torpedo decoy (Perry has
AN/SLQ-25 Nixie), or a
CIWS (Perry has a Phalanx Block 1B).
They have only a single
helicopter (Perry has 2, and of a more capable type).
They have an inferior L-band (1 to 2 GHz) air and surface surveillance
radar with instrumented ranges are 110 km for the air channel and 80 km for the optional surface channel (Perry has the an L-Band AN/SPS-49 air search radar with a range of 46km and an I-Band A/SPS-55 surface search and navigation radar with a range of 93km). They also have an inferior
electronic warfare and decoy suite in the form of ARBG-1A Saïgon and 2 Dagaie decoy systems (Perry has SLQ-32(V)2, Flight III with sidekick,
Mark 36 SRBOC, to be replaced by the Mk 53 DLS "
Nulka" missile decoy system, which will be even better than the present chaff). And they have inferior
speed (20kn versus 29+kn, which allows to Perry to operate with a carrier strike group is necessary).
Moreover, whereas it would be hard to increase the AShM load of the Florean, or to add SAMs, the Perry can be fitted with 2x4 Harpoon in a jiffy (it is fitted for Harpoon already) and with e.g. a 21 round RAM launcher with barely any work.