I've been through SYD I arrivals numerous times now and for most part customs are straightforward and easy to deal with. I always have something to declare, but even then they're good people to interact with. A couple of times I've been "prescreened" and let through.

My first time into AKL (or New Zealand for that matter) I got benched and of course got cleared of any wrongdoing (although the person assigned to inspect me at the time probably really wanted to do me in). Subsequent times, though, have only been x-rays (even though, yes - once again, I had items to declare). Really weird, and on travelling to AKL I still always prepare for the worst treatment.