Well, they will be cheaper to operate.
The Nigerians will get at least two of these. I believe the radar system is a British design, and those engines are German.
As their other major combatants/vessels, they have a German built Meko 360 H1, the NN Aradu, F89, and a refurbished Hamilton Class US Coast Guard Cutter, NN Thunder, F90, as their other vessels. The Aradu is an impressive naval frigate at 3,300 tons, with 8 SSMs and a 76mm main gun, which was built new and commissioned in 1982. The Thunder carries a 76mm gun too and displaces 3,250 tons. It was originally commissioned in 1968, but was refit, handed over, and commissioned by Nigeria in 2011.
These new built vessels, if well built and well maintained, will get more than 30 years service life out of them, as evidenced by the Hamilton class which are over 45 years old and still going.