There are other options than CTC or AFS in this geographical area. Take a look at Bay Flight Tauranga or Waikato Aero Club, both have good experienced CFI's and staff and they can do the student loan thing if you need that. I would recommend these over the other two places, they do a good job without all the hype.
As someone else mentioned go and see for yourself, make an appointment and check them all out. Just make sure you can sort out the sales talk from the complete truth.