Phone coverage in the outback
I'd definately recommend Next G. Few weeks ago I was flying Broome to Gibb River and I had coverage the whole way till i was about 3000' on descent into Gibb.
The Telstra $79 cap is the the way to go. You get $450 worth of calls (although telstra phone rates are ripoff so $450 doesnt stretch that far) plus you get a free samsung phone with built in MP3 player and 500 Mb memory card.