I've never heard of enamel or plastic sinks! It's all stainless steel here. New houses have twin sinks, one with waste disposal, and a lot have stainless steel bench tops, fridges, and ovens. I don't like it for those things myself; it's very hard to keep looking nice; one touch and it needs a wipe.

I've come across plastic bathroom sinks though.

I use plastic mesh too as it doesn't scratch.