So,
Who are you with, roughly how much are you paying, and are you happy with them?
I'm with Circle through a broker, was quoted nearly $1100 for this year's premium on a car only worth $4500 (PS13 Qs), and me with 3 years no-claims and a 100% clean record thus far, so went for third party at around $450. Main factor in the high price is apparently that I park it on the road. Since third party covers the same stuff full insurance does with regard to that, I'd say the $600 difference means that's a crock of shit.
I've had no interaction with Circle but I'm not happy with the broker -Hawkes Bay Insurance- as I don't think they're getting me a particularly good deal (shafted I think, actually), and they've been particularly slack with not sending letters, etc.
The policy is up in September, by which time I will hopefully have a new car anyway, so I think I'll look elsewhere then.