We went thought a bunch of shit when they rolled out ADSL2. Orcon fucked up, Chorus fucked up and neither of them could be fucked taking ownership. Our connection was basically fucked for about a month, with ongoing issues. It took us upgrading to a business plan to get better support out of them.
Having said that, when our connection is working fine (which it usually is now) it's great.
They do go through periods of their international bandwidth being overloaded however.

16-17mbit not unheard of on a good day. Also can torrent at 1.4MB/s on a good day, and sometimes not at all between 7pm and midnight. (Pitt Street, Airdale St exchange afaik)
Summary: better than most with small amounts of uselessness.