1, If you process with AAMI, normally you need to pay the access fee by yourself and then get your car repair and wait for refund (if you are not in the fault side)
2, Process with RACV after they received the access fee from another guy (if you are not in the fault side) and then you can get your car repair with no cost.
For me I will use RACV as I don't need to have record with AAMI.