I was on the lookout for a relatively cheap but good mesh system without a need for wifi 6, and this looked decent enough with good reviews.
I bought mine off Amazon as I had some wallet monies from giftcards, so I am not actually sure what coupons apply to this deal but there are a bunch to try.
Description (copied pasted):
Deco is the simplest way to guarantee a strong Wi-Fi signal in every corner of your home up to 6,500 square feet. Enjoy fast and secure Tri-Band Wi-Fi no matter how many devices you have. Deco M9 Plus connects and controls your smart home devices as a hub, no need for an additional hub. Three separate Wi-Fi bands deliver super-fast, stable connections to devices in every room of your home. More bandwidth is freed up with dedicated wireless links between Deco units. Say goodbye to lag with AC2200 Wi-Fi system. Deco M9 Plus uses not only 5G_1(867Mbps) as wireless backhaul but also 5G_2(867Mbps) and 2.4G(400Mbps) as backhaul while traffic gets heavy, delivering speeds over 1000Mbps which is ideal for your gigabit fibre. Eliminate weak signal areas with whole-home Wi-Fi. With an ever-increasing number of bandwidth-hungry gadgets in our homes, you need a network that can rise to the challenge. With network speeds three times faster than the previous generation routers thanks to 802.11ac wireless technology, Deco can provide lag-free connections for over 100 devices. Deco units work together to form one unified network. Enjoy your smart life not just in your living room, but all around your entire house with Deco M9 Plus's s smart mesh. Deco M9 Plus acts as a smart home hub, bringing all your products together in one easy-to-use app. Set interactions between Zigbee, Bluetooth and Wi-Fi devices. With Deco M9 Plus, enjoy the magic of the smart home in every room. TP-Link smart devices, GE, Kwikset and other leading brands are supported, making possible a range of interactions between bulbs, locks, cameras and more. Unbox Deco, install the app and then simply follow the on-screen directions. Deco will take care of the rest, getting your network up and running in minutes.
AU $246.50 with PLUSTJA coupon code. Plus membership required.