I got my PPL in New Zealand and my 100 hour building for my JAA (f)ATPL.
For its size Kiwi land has quite a few flying schools. I have knowledge of the IAANZ and serveral of my friends went there. They set the standard very high there to that of the equiv of NZRAF courses. They have no nonsense and if you find things hard have no hesitation to kick you off the courses even if you're preapred to work or are working very hard. They turn out good pilots (or throw out mediocre) but it is very pressurised and there is no real personal attention. Ardmore I have been told ahs a very similar tin can factory approach.
From what I have witnessed and I won't give too much away about myself Nelson Avaition College is situated in the beautiful Motuaka and is a very nice relaxed college with a great student buz. Another good school is Flight Training Manawatu - a very personalised approach and friendly school with no pressure. In Christchurch, there is an up and coming school in Wigram which is really friendly and now has multi-engine aircraft and full time courses. You can complete your courses here in half the time. The above three are just a few to mention but in my opinion they are schools where you can really enjoy your flight training. There is no uniform or hierarchy where the instructors have one room to have their lunch and the students another. Beware as well that the main so called 'premier school' you are mainly trained by 22 year olds who have just got ther C Cat 2 months before you started!
I hope this helps. I would like finish by saying that different peoples personalities suit different environments. So IAANZ or Ardmore might be right for you - but ndeffinately not for me!