I've just been reading with interest this old thread,
http://www.geekzone.co.nz/forums.asp?ForumId=49&TopicId=19379&page_no=2
and wondering if there are any more up-to-date thoughts on this.

One thing I'm not clear on, they're not very far away from the neareast cabinet with an ADSL service, but of course it is all relative! Following the most direct route by road (and most of the distance it is likely to be a direct route, being a rural area and there are not too many options for long detours), they're perhaps 3800m from the cabinet. To be conservative, I'll assume it's somewhere under 5km. There are people 1km closer who definitely have ADSL, so it seems somewhat likely that my parents might be close enough? And that they might get better speeds and prices with ADSL over wireless. I have been thinking about getting the people they know to run a speed test, to give some idea of what might be acheivable.

I have a spare crappy modem router, so I was thinking of finding a non-contract ADSL package to see how it works? Any better suggestions?