I have used plated tips on my mig welder for many years and they never seem to give any problems, but where can you buy them.? They all seem to be unplated copper now.
Miike.
The plated ones used to be used with aluminium, they were supposed to reflect the heat away from the tip, they also resist spatter a bit better, no advantage using them on steel, never really noticed much difference on aluminium either.