From my experience, it is easier to buy an unlocked phone, and then use whatever SIM you want.
I have NEVER had a locked phone, always buy unlocked, and transfer my SIM as required!
Currently with Telstra on the $30 pre-paid plan - auto top-up every month, and have never used the limit (data or calls) even with trips to Japan!
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If you had to choose between being fit and drinking wine ...
most service providers say they use the Telstra network but dedicated Telstra users are given preferential access if the service gets extremely busy. Typical example is Lakes Entrance over Xmas when the town grows by thousands. I am with both Telstra and Aldi and sometimes had no access for internet using Aldi while Telstra worked fine.
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Jenny and Barry
2009 Roma Elegance / 2013 Colorado. Permanent travellers 2011-2015 now just travel for 4-6 mths
Yes it will be interesting although probably predictable.
The OP asked about SIM card fittment but we still hear how that if you pay up to 3 times the cost for a Telstra account you will have better service.
I am currently running the two accounts side by side and over 4 states I have not seen one difference. While we are driving I get the navigator to watch both services and there has been no difference reported between the two accounts.
I will keep the extra money and buy a beer or two although with what I save I can buy 3 cartons a month
It should be noted that I do not have an Aldi account and my comments can only reflect the performance of Boost.
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"Seek the truth or bury you head in the sand, both require some digging"