In my opinion,apart from the packaging that makes these two different from each other I think the taste and filling also make Australian Cadbury Chocolate more tastier than Malaysian one.
I prefer Australian Cadbury Chocolate more than Malaysian due to the filling in the chocolate. Every bite you will get to eat the nuts,marshmallow,cherry jellies, cookies, coconut,almonds,hazel nuts and etc.
And for all Muslim,as far as I concern the chocolate does not contain any prohibited ingredients such as liquor and they got international HALAL certificate. InsyaAllah there is no doubt about it.
I am a big fan of chocolate! Everyday must eat chocolate at least 1 small bar :)