Firmware advice Nighthawk AC2200 x6 R8000 and EX8000 extender

New ISP May 3rd

Replacing current Linksys complicated large home and property with 2 metal out buildings.

In anticipation I bought ON SALE via Amazon: 1 R8000 NIB in 2021, 1 Refurbished R8000 this year, 1 Refurbished EX8000 extender in early 2022. All with Amazon Asurion electronics warranty AND 6 month subscription to NetGear Gear heads support.

I bet none of the three has current Firmware. But right now no Idea of current version.

I down loaded from NetGear the recent firmware:

EX8000-V1.0.1.240-------------------- Feb 2022

R8000-V1.0.4.76_10.1.82 ----------- Feb 2022

R8000-V1.0.4.84_10.1.84 ------------April 2022

Question in a minuet----

My intent before the network NEW set up with NetGear vs Linksys:

Log into each device

Update firmware's first

Change device log in password to different from default

Change SSIDs and WEP3 pass codes and Guest passcodes

Based on all the discussions here I am concerned that the R8000 firmware ------.84 is a mistake for DNS reasons that in my configuration WILL be a challenge

Proposed connectivity

ISP to 1st R8000---Cat7 to 2nd R8000 in AP mode inside same house---Cat 7 from 1st R8000 to 150foot distant Metal shop EX8000---Cat7 from 1st R8000 to Outdoor off brand AP for outside 2.4Ghz cameras----5Ghz Wifi from one ( best 5g signal strength) of main house R8000s to closer 55 foot shop Linksys extender (my current extender in this shop is connected 2Gzh band and plenty to watch streaming TV

The question

What firmware does the group think will be least problem?