Hey John P
long time no see!! Glad to see you following on with the NZ trip! Best time?? having been there, don't see how there could be a worse time?? We went August (damn cold but what we wanted after our beach lifestyle) but depends on what you want! Personally we now want to see the other seasons there as we can imagine the beauty!!! our pics are in the places directory (or cheat and peek here -
http://www.flickr.com/photos/rosscher/sets/72157607000848540/).
We "lucked" the weather - it is a high rainfall area so be prepared!
Email us if you want more specifics but otherwise can't see how you and your better half can't have some fun (and besides time the new 50D - if I remember correctly - got dusted off!!)