when the powder coat starts to lift it peels off in big chunks i would imagine that trying to respray would look a bit naff,better to wait untill the unit requires a rebuild and get it blasted and recoated at the same time
Even worse when alloy corrosion gets under the paint it runs riot and chews into your metal under a harmless looking bubble.
If its the same paint they use on the wheels, shot blasting will gouge the underlying metal before the paint is cleaned off. My powder coaters did a test and pointed me straight to -