The major disadvantage to winter touring isn't the temperature, but the short days.  On the drive from the seals, we were too late to see the Buller Gorge Swingbridge, but had to navigate the winding mountain roads in the dark.  On the road to Abel Tasman in the early AM, we again had winding roads in the dark, with the added challenge of black ice.  The cold empty motel in Murchison reminded me of the motel in Durango that we stayed in one winter when we had snow chain difficulty and couldn't make it to the condo in Purgatory.  The drive Saturday AM reminded me of a 180 in the Audi on the way home from Angel Fire.  Rich did a great job driving, and got us safely to Marahau.

After an informative ride, we were dropped off at a beautiful beach, and walked to our pick up spot at another beautiful beach.  For those on multi day walks, there are huts and campgrounds along the way.  We walked from Bark Bay to Anchorage.  Took the low tide route, but missed low tide by a couple hours, so had to take our shoes and socks off while crossing the estuary.  Brrrrr.
Don't skip these pics: https://picasaweb.google.com/115133267095590644390/AbelTasman?authuser=0feat=directlink

Driving to Picton, we took the scenic Queen Charlotte Drive instead of the state highway, which turned out to have more twists and turns in the dark than ever.  The motel had electric blankets, and the bed was close to the heat pump, so we were comfortable.  Motels in NZ have kitchens, and you're given milk at check-in (regular or slim).
In restaurants, be sure to go up to the counter when you're ready to pay, or you'll be waiting at your table for the check for a long time; and don't forget that there is no tipping.