Does anyone else have a problem with the ozpost module being somewhat steep on delivery pricing?

I have set it up in a test environment and configured one item as follows:

LxWxH = 25cm*20cm*18cm (actual size)
Weight = 3Kg

Delivery and receiving postcodes = 2450

I then checked the Auspost website based calculator and got:
Regular Parcel = $7.95
Express Parcel = $10.20
Express Platinum = $14.40

The Ozpost module gave me:
Regular Parcel: $16.45
Registered: $19.25
Insured: $42.45

I have all handling fees set for $0

Any ideas?