Tom Tom - Europe and Australia query

[Tizer]

Hi,

I'm looking to buy my first Sat Nav which will help me when my wife and I head out to the Italian Lakes and Milan next month - I've identified a few that have Western Europe maps which is just the ticket.

However, we do have a driving trip planned around Australia and New Zealand and I would like to be able to use a system which I can download the maps for these countries on.

The last thing I want to do is buy a system which I cannot download the maps onto.

Preferably, I would like a Tom Tom.

Thanks.