NonprayingMantis: you need to be careful about that 'Fair Use' policy.
Orcon had to remove it from their unlimited plan under threat of the comcom, and no other ISP has it.
That suggests to me that having a fair use policy on an unlimited plan probably breaches the fair trading act.
You might be small enough to slip under the comcom's radar for now, but not for ever....
Our marketing has always been "unmetered" not "unlimited".
The service is unmetered from a billing perspective. We never charge for excess data. It's not unlimited in terms of download the internet and expect a consistent service all month long.
Our contracts have always been up-front about the fair use policy as well.

