OK, camper review. As above, wife had her doubts going in but is now one of the converted. This was the first time either of us has done a campervan holiday and it was great.
We went with Britz. First tip, Maui, Britz, Mighty and (maybe) Jucy are all owned by the same company apparently. Don't go with Maui. They are the most expensive and I assume people get the impression that means they're better, but here's the tip: After a Maui van has done so many km or a certain period of time (not sure which) they are repainted as Britz vans and the price goes down considerably. Our van, and most of the Britz fleet, was a VW and you could see where they'd painted over the Maui markings, from what we saw, it was very similar to the newer Maui vans internally (the main difference being that most of the Maui fleet were built on a newer Mercedes chassis/engine). The only difference being it had 100,000km on the clock and was therefore a bit older. But without the km as an indication, you wouldn't know it. Fit out was near identical and there was certainly no difference in comfort or amenity that we could see.
With the three of us we went with a 4 birth "Explorer"
http://www.britz.co.nz/campervans-nz/Pages/explorer-4-berth-campervan.aspx and it suited us fine. It was roomier than I expected and quite comfortable. That said, I wouldn't put 4 adults in it at once. The fridge worked well both with 240v hooked up and running on 12v. One tip here, don't store bottled beers on their side, I had 2 get sufficiently shaken up in transit to leak (however they were both ringpull so this may have been a factor). We didn't use the shower as we were in parks with shower blocks at least every second day and the toilet is strictly emergency use only as you're the one who has to empty it. That said, it's a capsule style, so it's not that big a deal, just pull the capsule and pour it down a designated dump station, give it a rinse and put it back in. Recommend getting "the bundle" package for an extra $10/day. Gives you snow chains, picnic table and chairs, kid's seat (if required), 1GB wifi, free linen exchange at their bases (Christchurch and Queenstown on South Island) and additional driver. Also recommend the express return pack ($249) as it means you take it back dirty, toilet full, waste water full, gas bottle and fuel empty and just hand over the keys and walk away. This price also covers the road user charge (they don't have tax on their diesel at the pump) which comes in about $60/1000km. We did a little over 2000km in 2 weeks so half the price of the express return was eaten up just by this charge, well worth it.
There was a diesel heater in the van that you can run when parked up and not plugged in, but we only needed it on one night and there was a fan heater supplied you could use on 240v. Cooking in the van was easy with a gas stove top and all necessary pans and utensils supplied. We did about half our cooking and eating in the van and the other half in park facilities. Dinner table was stow away under the bed when not in use and easy to set up and pack away.
If you're going, download the Rankers app on your phone and take the time and bandwidth to download the maps. It shows all the camping spots in the whole country with reviews for each so you can be informed before you go to an area about your camping options. There are a lot of "freecamp" options around the country which are areas you can camp at no cost but you must be in a self contained vehicle (which most, but not all, vans are). We did a mix of freecamping and parks. The advantage of parks is shower blocks, kitchens, wifi (although you can opt to purchase some wifi with the van) and 240v power (which recharges your house batteries and allows you to run the microwave, fan heater and other appliances such as phone chargers). Parks charge by the person, not by the vehicle, average overnight price for us was somewhere between $45 and $50 for a powered site. Most parks had pans, crockery and cutlery in their kitchens for general use which made life easy as you didn't need to get yours out of the van.
We had 2 minor issues with the van which were sorted quickly and mostly pain free. The hatch/vent above the top bed (above the cab) was leaking around the seal, we rang them (free call hotline) when we noticed it in the morning after some rain overnight, they asked us our plans for the day and we said we wanted to move on to another town some 280km away, they arranged a place for us to take the van on the way and it was fixed quickly with minimum hassle. I'd fully expected them to tell us to stay put for the day as we were in Nelson (major centre) at the time and were travelling to Hokitika that day (very small and remote west coast town). They had us get it fixed in Greymouth where we would have stopped for a break anyway. Second issue was the cradle for the Tomtom crapped out on the day we traveled to Queenstown and wasn't charging. Stopped in at their base in Queenstown and it was swapped out, no questions asked. We would have gone to the Queenstown base anyway to swap out our linen as we were a week in at this stage.
The only down side I can really say about the van is they are very thirsty. Fill a tank with about 70L and, depending on conditions, we were getting 450km at most and as low as 380km on one tank. This is probably not surprising given the size of the vehicle and the nature of the windy/steep roads over there (it wasn't much better on straight and flat), but it can catch you out as it nearly did for us when I had half a tank left leaving Haast and we coasted in to Wanaka on fumes. It drops very quickly when the (digital) gauge gets below halfway. Those who know this road will know you cross a mountain range on this trip, so that has a bearing, but I thought half a tank would cover it easily and was very nervous watching it drop on the way up (fuel stations are few and far between on this stretch).
Finally a tip on travel times. I knew it took longer to get around distances in NZ due to windy roads but didn't realise just how much longer. Pay very little attention to KM between towns in relation to how long you think it will take. One stretch of 100km (pretty much all highway) took us about 2.5 hours due to windy roads. The Tomtom was pretty spot on in this respect for estimating times and after a day or so I learnt to trust its predictions. Being used to the Bruce highway in QLD for most of my life, it came as a bit of a shock.
All in all, highly recommend it, will come back later with more info about where we went and what we did.