'sorry, don't have much for you regarding the brands/bikes you mentioned but I think there's a way to search by member location and I've seen some fellas from Perth hang around here?
High end for your description would be Optibike or something called the Stealth Fighter/Bomber? Of course, you need to decide and mention if you wish to stay totally legal or push boundaries a little? I'm sure the bikes you mentioned would fall in the "legal" category for AUS but many people don't enjoy those power levels nearly as much as +1000W stuff.
So, fill in with what you want to do with your ebike, read posts, look for local peeps to try things, read posts, ask questions, read more posts, would be my broad advice.