Wife was on the old Telstra Pre Paid Extra which wasn't a good deal by any means, but we were sitting on a pile of recharge vouchers so we didn't want to move anywhere else until we'd spend them all.
Now Telstra quietly updated their main prepaid offer to Telstra Prepaid Pre-Paid Max. That includes 8GB per 28 days with data banking up to 200GB which doesn't expire (although requires an active recharge to access). So we've switched to it for now.
It's normally possible to buy a $30 Telstra voucher on eBay with 20%-30% off (see this forum post, currently selling for $21, bought from them myself a few times - can vouch). Plus take an extra 10% off during regular eBay sales, plus maybe another %5 off using discounted eBay gift cards, that potentially brings the cost down to $17.96 per 28 days.
IMO, that's a better deal than the current Boost offers, and it's still on the full Telstra network with VolLTE/VoWiFi and roaming (for which we care as we want those 2-factor authentication texts while abroad). Wife still has ~30GB of data sitting in the databank from her past Telstra Pre Paid Extra recharges. It's always possible to bank it up on demand, e.g. 38GB for $48 (a discounted $60 voucher from the same seller).
So now I'm thinking, maybe I should keep her on Telstra Prepaid Pre-Paid Max, and maybe I should even move there myself once my Telstra contract is over. I could even set one up for my old folks to be used an alternative to NBN, as they're really not data hungry.
And if that seller disappears, there's always a bunch of good offers to choose from these days.
Not posting it as a deal as it isn't compliant with OzB policies, but thought I'd still share it here.
Not sure if useful as its probably cheaper with the vouchers but if you use the automatic payment option online for your prepaid, and set it up once a month (say to recharge every 2nd of the month), it will actually increase the 28 day limit. So instead of it being 28 days, its however many days in the month (30 to 31 typically) or at least it does so for me with my current plan.
Could be useful for people like me who are a bit more lazy and get the added days in a year.
Breakdown over a year:
28 days payment – 13 payments a year of $30 = $391.07
Monthly recurrent version = 12 payments of $30 = $360
Saving of $31.07 a year (and about $40 a year for the $40-dollar plan) doing the online recurrent payment (You save a month)
Though OPs way is better
28 days – 13 payments of $17.96 = $233.48
Saving of $157.59 compared to normal 28 day payments in a year being the obviously better choice if you can do it.