I'm tempted by Slingshot's new $69 phone + rollover broadband plan. I'm not sure what I'd do with a 500GB Mega account though. The one thing that gives me pause is reading poor reviews of Slingshot. However, they were almost all >1 year old, so has Slingshot upped their game recently?
If not that, I guess I'd probably go for Vodafone's 80GB naked broadband + their cheapest phone contract for the $30 discount. So $94 for 80GB + a phone contract.
I'm still concerned about guests using too much data. But maybe a simple solution might be to change to an unlimited or ultra-high data plan in high periods and forget about trying to cap it?