Just to add to the 'next g' coverage issue, the handset you use makes a huge difference. Do not believe the Telstra 'blue tick' crap either. In my experience the LG (which is blue tick) and Telstra branded models are crap from both a reception and reliability point of view, the I-mate suffered poor reception and sometimes when I lost service it wouldn't search again unless I reset it. The Nokia's are pretty hard to beat especially the E51 which I got a full twelve months out of (which is good for me) it even went through the wash in the first month. Very rugged phone and I have never not had service while someone else did at the same spot. I'm that impressed by it I bought another one when my first finallly died. The N95 or 6210(i think) have pretty good reception also but I doubt either (particularly N95) would survive my neglectful treatment.
Just my $0.02
PW