huawei ax3 is a main router, u get 2x units, 2nd unit act as mesh, connect via wifi.

disadvantage of huawei, based on my experience of wifi 5 ( i dont have wifi 6 device)
- coverage wifi area is slightly smaller compare to asus ac86u, i tested it  based on installing 1 ax3 vs 1 asus86u.
- compare using lte discovery app, asus can hit 103 dbm in my master bedroom, whereas huawei ax3 can only hit 98dbm
- in my master bathroom, double wall, huawei ax 3 will lose connection sometimes.. vs asus ac86u can do casual surfing, loading will take longer but didnt lose connection.
- dont have extra features unlike asus offer u to tweak this n tat via ur router, the router setting is very clean cut and simple.

i am using ax3 2 units, 1 located ground floor, another 1 i put it on 1st floor located at the middle of the house.
covered whole house, no dead points. i stay in double terrace, size 24x75 fyi.

ax3 can be control using the mobile app - ai life, just download it and other is quite simple.

i wanna get the ax3000 asus at first but after a few thoughts, aiks its time to cut cost and tighthen my pocket...
overall i am quite happy with the huawei ax3 , with 2 units of ax3 i got no issue on playing games with low latency + youtubing + movie streaming at the same time.
whereas

tp link deco required u to connect 1st deco model via cable to router, then only 2nd unit can connect to 1st unit deco via wifi, to me u gotta get 3 units of deco unless u have very long lan cable to connect the deco unit and move it to the position u preferred.

I place on the area where we use the wifi most.
1 in the living hall, and 1 on 2nd floor (outside the bedroom)

So the weakness is kitchen (where we seldom use wifi) becoz there are double wall, coverage soso only restricted to 2.4ghz
Whereas 2nd floor, 3 bedroom both getting 5ghz channel with good wifi coverage, theres only 1 wall in between the 2nd router.

If u wanna make it perfect then setup the 3rd router on kitchen to cover the 5ghz deadspot.

I never use x20 before so i have no idea how good on its coverage area, but it seems like kinda pricey ofcoz it ll definitely hav its own advantage.. Gotta ask those who r using it get their feedbacks.

What i know is that if ur unifi / fibre r only 300mbps or below, ax3 pro is a good option though, it doesnt comes with fancy festures like the asus do (those vpn, gaming extra feature) however its very easy to handle and setup.
Take note that if u have double wall or trible wall, ur wifi coverage experience will suffer alot.
I would suggest u to start with 2 units (be it x20 or ax3pro), then if its not up to ur standard u can add on the 3rd unit to fix ue dead spot.

Fyi i m using 2 unit of ax3  pro to cater 12 devices in total,  so most of the time 2 units are under constant load and i have no issue on the gaming experience despite so many users using at the same time, all you need to do is to control the device thats utilized all the bandwith.

What i like the ax3pro is that it can set automatic turn off at certain hours, whereas my old asus router juz doesnt seem to hav such feature yet.