Noticed that the iPhone SE is $150 off, similar to this deal https://www.ozbargain.com.au/node/550568 but it wasn't discussed there and I thought it worth attention.
Usual caveat that it is technically purchasing with a payment plan linked to the contract. Factor in that you'll need at least one month (unless you're lucky and get prorated) at a minimum $35. Still makes it $634 which, ignoring the oddity and mental gymnastics of the Optus flybuys deal, makes it a good price.
@[Deactivated]: How do you compare speed in practical use?
You get 1/2 functionality from Android & cannot transfer out without pain.
On Android, you can change to any brand in very short time, with most apps free.
The speed comparison is false economy. Minor benefits are too costly.