I know it does not always work out cheaper ,sachels can be cheaper in the long run,  i dont do a lot of sending out as most are pick ups  , here is 3 parcels i will be sending on monday.

16kg to s/a courier $11.30  AP  $30.35........   2kg to tasmania  courier $15.10    AP $15.85..... 2kg melbourne   courier $6.75    AP $10.05.