Billion are better now than what they were about 5 years ago.
Unfortunately their official line of support for quite some time was to "update" the firmware.
Been using a Netgear DG834 (old but works perfectly and has been the most stable modem I've ever used) modem/router and a TP-Link wireless access point which is sitting behind the TV in the middle of the house.

Don't know why, but I'm not a huge fan of All In One hardware packages, if one thing fails, it pulls everything down with it.

Assuming you are on iiNet's on-net plans (Chime DSLAM) I would invest in a modem that features a broadcom chipset.
This will give you the greatest stability (independent of your lines attenuation and SNR on the downstream and upstream).

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2020 VW Tiguan Allspace
teejay: If I wanted a comeback Id wank in front of a fan