Hi sifus. Super lurker here.
So after researching around for weeks, I'm kinda leaning for the Zyxel NR5103e at this point of time (at least for the sub RM 1000 price range).

Feel free to inform if you encountered any of these/solved the issues/have daily annoyance with any of the routers mentioned.

My concerns here are mostly on day to day stability since that's a common factor that anyone can relate with while speed is practically YMMV.

So I start my findings with possible issues first:

TP Link NX510V
May auto reboot itself - https://old.reddit.com/r/TpLink/comments/18...booting_itself/
Corroborated by threads in here. Can be very disruptive if working remotely and in meetings

TP Link Deco X50 5G
Disconnection issues with red light displayed, possibly due to carrier setting being set to "auto": https://community.tp-link.com/en/home/forum...replyId=1327572
Purported fix is to just set the carrier yourself.

Arcadyan AW1000 - Custom OpenWRT is still very WIP: 
I scanned thru the main forum with latest discussion - https://forum.openwrt.org/t/arcadyan-aw1000...-ipq807x/122307
Might be some key things to look out for - https://forum.openwrt.org/t/arcadyan-aw1000...q807x/122307/75

Nokia Fastmile (v1)
May need to lock-in these settings: https://forum.lowyat.net/index.php?showtopi...ost&p=109104026
I remember seeing a post where the modem may switch to 4G haphazardly. Since it has no band locking, this may be a major issue.
Second factor: Heat management, especially for those who'll use it as sole 5G + Access Point
Have internal fan:
Zyxel NR5103E - Disassembly: https://www.ispreview.co.uk/talk/threads/zy...assembly.38870/
TP Link Deco X50 - Disassembly: https://www.blacktubi.com/review/deco-x50-5g/
TP Link NX510V - Disassembly: https://www.blacktubi.com/review/tp-link-nx510v/

No fan inside:
Telstra 5G Arcadyan AW1000 - Disassembly: https://www.youtube.com/watch?v=zdhK0ypTaOM