Im planning on getting a Telstra card, as I will be travlelling to Syd, Mel, Tas, Kakadu, and Cairns all within 3 weeks and this seems to be the most solid choice as far as coverage goes. I also only want data. Any thoughts? It seems that I should just go to a telstra store when I get there, but I think I can just buy a telstra nano sim anywhere and just recharge it if/when I need more data? More concerned about data coverage first, then cost second