Cheapest it's been in a while. If you can price match at JB or TGG's and use 15% giftcards from https://www.ozbargain.com.au/node/800798 then the price per speaker is down to $208.25 which is very good.
I think Videopro might be matching the Sonos site sale which ends the 2nd Oct.
i would rather buy a gamecube
Black is 499 (delivered) at Sonos -> https://www.sonos.com/en-au/shop/two-room-set-one-sl
Actually - JB is offering 2 for $499 too! (applied at checkout)
You are right. You can use the perks $30 off $300 spend, then pay with a gift card. This brings it to under $200 a speaker. So an even better deal.
Id rather spend my money on a GS