Their highest model(WP660) with the best price, lower model ultra plus is right now $129 @shavershop as a promotional offer.
Normally 170 @Amazon AU, so you can save $65 if you buy it today, don’t forget to pay with 3% off gc which is available via Suncorp and Cashback from Cashrewards which gives Cashback even if you pay with gc this time.
Amazon AU is also selling the cordless version for 115.1 now(normally 150), the highest model WP560, but I guess either one of them would be enough.
https://www.amazon.com.au/Waterpik-Cordless-Advanced-WP-560-…
got one, thanks