Yup, Chris, the Scottish tourism industry will be drafting hate mail for you now as I type!!
New Zealand does not have a large temperature range, lacking the extremes found in most continental climates. However, New Zealand weather can change unexpectedly—as cold fronts or warm tropical cyclones quickly blow in. Because of this, you should be prepared for sudden changes in weather and temperature if you're going hiking or doing other outdoor activities. In some respects, it is better to carry 'too much' warm clothing rather than too little, but I'm always prepared for hot weather too, even in winter!
However, I still like the ideal of the Paramo clothing, but I wonder why it needs to be so heavy and thus warm? Maybe something to improve on in future. If it were lighter, it would also likely be less warm and therefore more versatile over a wider range of temps. I would dearly love a fully breathable lightweight waterproof jacket for hiking up hills in mild to warm rain...who wouldn't???
The technology kinda reminds me of the good old Swandri coats that outdoor workers used to wear. It was thick and rough, but the fabric's natural lanolin and semi-felted texture made it very breathable yet fairly water resistant (but warm and heavy).