Usually it’s £129.99 (which is good value) but Amazon has knocked £35 off for Prime Day making it just £95.
That’s not the cheapest we've ever seen it - it was £89.99 on Black Friday, but it's still a good price for a three-unit mesh Wi-Fi kit.
The Deco S4 claims to cover up to 4,000 square feet and it also benefits from Alexa integration (for the guest network password) and has a decent app. There are two Gigabit Ethernet ports on each device, too.
One point to bear in mind is that the two satellites communicate with the primary directly, so this system is best installed in a 'hub-and-spoke' configuration where the other two units can be placed where they still have a strong connection to the main one, rather than in a line with the third one furthest away.
Also, unlike TP-Link's more expensive systems, such as the P9, this doesn't use powerline networking tech to communicate using your home's mains wiring.
Nevertheless, with speeds of up to around 170Mbps, which is way faster than most UK broadband connections, then this budget mesh system is a bargain and will deliver considerably better Wi-Fi coverage and speeds around your home than an ISP-supplied single router.