I was in Wellington the other week to catch up with friends and family and had the opportunity to catch the new Matangi trains out to Johnsonville – you might remember my previous trip out there featured the pre-WW2 relics, so it was exciting to check out some 21st century transportation. :-)
In some ways, it’s sad to lose the old relics since they were great fun as a visitor, but I can imagine that the local are grateful for some of the more modern comforts and quietness.

I do think showing the train's model name rather than the actual destination is going to be pretty unhelpful for tourists, I'd be pretty worried if I was trying to catch the "Johnsonville" train if it had a sign saying "Matangi". :-/
Of particular interest is that the Johnsonville units are specially marked, as they feature an additional feature of “wheel flange lube” – apparently this is to help deal with reducing wear on the tight Johnsonville line rails by keeping the wheels lubricated.