Did 7 weeks in South Island, NZ last year. Fab trip, great scenery, plenty of good sites available, controlled ‘official’ wild camping spots, friendly people, in general no parking issues in towns, roads (including some of the main routes) a bit hairy in places.
Hired a one year old 7.5m coach built - quite expensive. Many self builds including bus conversions on the road, also many converted estate cars and MPVs.