I tried '3' but had no service on Central Coast that covered more than a few towns, then Vodaphone, but over 12 'drop-outs' per call while on the F-3 (used 'hands-free'!), and AAPT, but crappy range, ane even 'Virgin' but smae problem, and all the above had crap broadband speeds.
Telstra charge craps, but.... speed is best, and coverage is everywhere (even tamworth, Gympie, F-3 etc where all the others failed) so you get what you pay for...(though it's a cent a minute in Asia etc so rates are high in order to pay bribes to government officials, same as the pharmaceutical companies charge exoprbitant rates for their killer medications)