Should I paint a new radiator before fitting ?

[silverdale]

I have to replace a tiny 400 x 500 rad in the downstairs loo, its a cold room. I replaced it about 4-5 years ago but this 2nd one has gone the same way, rusty I put down to condensation. I just wondered, should I try to aerosol spray paint it with some protective rad spray before I swap it out or simply replace if and when ?. I want to sort it before I sort the heating out with inhib etc,this year.