18 months ago when I signed up with Virgin Mobile  the data transfer quotas were 200MB on the $29 per month plan and 1.5G on the $39 per month plan. About 4 months ago when I checked the prices the amounts of data had gone up on the same plans (2.25G for $39 per month from memory). Now $39 per month gets only 500MB! It seems that recently Virgin has significantly reduced their value for money.
Virgin does have an option to pay an exgtra $10 per month for 2GB of data which gets you 2GB per month if you sign up for 24 months. That is reasonably good value, when I first signed up with Virgin I paid $39 per month to get extra data transfer, now I could use the $29 plan for phone access and spend $10 per month on data with a Wifi gateway device.
On top of this the phone plans aren’t nearly as good value as they used to be. When I signed up with Virgin the Sony Ericsson Xperia X10 was “free” on a $29 plan, at the time that was a hell of a phone. I believe that the Samsung Galaxy S3 currently occupies a similar market position to the one that the Xperia X10 did 18 months ago – so it shouldn’t be much more expensive. But Virgin are offering the Galaxy S3 for $21 extra per month over 24 months on the $29 plan – a total cost of ($29+$21)*24==$1200 while offering the same amount of calls and data transfer for $19 per month ($19*24==$456) when you don’t get a phone – this makes the price of a Galaxy S3 $1200-$456==$744 while Kogan  sells the same phone for $519 + postage!
The cheapest phone that Virgin is offering is a Galaxy S2 for $5 per month on a $29 plan which when compared to $19 per month for the same plan without a phone makes the phone cost ($5+$10)*24==$360. Kogan sells the Galaxy S2 for $399 so there’s a possibility of a Virgin plan saving some money over buying a phone from Kogan. But given the choice of $360 for a Galaxy S2 from Virgin and the Kogan prices of $839 for a Galaxy Note 2, $349 for a Galaxy Nexus, $469 for a Galaxy Note, $529 for a Galaxy S3, and $219 for a HTC One V I find it difficult to imagine that anyone would think that the $360 Galaxy S2 is the best option.
I’ve previously investigated dual-sim phones for cheap calls and data  but they didn’t seem like good value at the time because the “free” phones offered by the telcos used to be a good deal. Now it seems that none of the telcos are offering good deals on phones so with my needs the way to go would be to buy a Samsung Galaxy S3 or Samsung Galaxy Note 2 from Kogan, and get the $19 plan from Virgin – probably with a $10 per month extra fee to get an extra 2GB of data. For my wife the best option would be to keep using the Xperia X10 on a $19 per month plan as she doesn’t seem to have any problem with the Xperia X10 that justifies spending hundreds of dollars.
I idly considered getting a portable Wifi-3G device to use a cheap pre-paid 3G data option ($10 per month) and a cheap phone plan without data (maybe $10 per month), but decided that it’s not worth the effort. The Virgin $19 plan gives me free calls to my wife and lots of calls to other numbers (more than I can use) and an extra $10 gives me all the data transfer I need. To use a Wifi-3G device would involve buying such a device and the hassle of carrying it and using it, that wouldn’t save money for at least a year and would be annoying.
The sudden decrease in data quotas is a real concern though. It’s an indication that the telco cartel in Australia is pushing prices up, that’s not a good sign. LTE is nice, but 3G with better quotas would be more generally useful to me.