The current version of the Deco X20 on shelves is mainly v4.
Intentionally or not TP-Link Retailers have NOT been made aware of the differences, as such the listing still advertises features that do NOT exist in version 4.

Specifically;

  Half the CPU cores and runs at significantly slower clock speeds (ie: Dual Core 1ghz vs older Model was Quad Core 1.5ghz

  Does not include Anti-Virus (now a paid subscription), since like v1.2 I believe.

I get the CPU shortage, but to-date TP-Link have NOT directly answered people when they ask for the HARDWARE differences between MODELS, instead respond with Firmware differences.

I will ask again directly, what are the hardware differences between hardware versions?

Here is what I could ascertain, but no details on RAM, which would be important with many on-line gamers.
v1     Free Anti-Virus with 1ghz Quad Core CPU
v1.2  Free Anti-Virus with 1ghz Dual Core CPU
v2     Paid Anti-Virus & Quad Core 1.5 Ghz CPU
v4     Paid No Anti-Virus & Dual Core 1.0 Ghz

I am considering this product, but wondering if I should spend effort locating a v2 unit with the Quad Core 1.5ghz CPU or will the v4 slower 1.0ghz Dual core CPU suffice.
Usage will be with a gigabit connection, and around 80 devices, 20 with WiFi6.  Considering the 3 units with wired Ethernet connectivity

Are there any performance comparisons? Happy for a much slowe processor if the units perform the same due to other improvements.

Eero published they were forced into a similar position (Quad to Dual) same CPU speed due to the chip shortage, but were able to expand the SOC functionality to perform more processing on-chip, eroding most of the performance difference.  They do acknowledge that the lower core count, will impact device speed when a large number of devices have connected.

Given TP-Link have both halved the CPU cores and significantly lowered the speed of the CPU, and official explanation is requested, especially while stock of v2 can still be found.