@pb9 I have been reading your other thread about your issue, I wish I had the knowledge to fix it. I have the same router as you, and it is honestly the most stable router I have ever owned.
I find your case very strange, as I happily use 160mhz and DFS channels, and suffer no disconnections anywhere, and I have over 50 devices.
Reading your thread, and I am only guessing here, it looks like you may be suffering some kind of strange wifi interference. All kinds of devices can cause this ; wireless phones, microwaves, wireless speakers, baby alarms etc.
Or perhaps there is a cable issue, or corrupted or incorrectly set up firmware. It could even be driver issues on your computers as you mention. Windows has a habit of updating wifi drivers to ones that it thinks are better but they are not for example. I stop my intel AX card updating automatically in view of this. There is also a possibility you just got a duff device, this does happen and should be RMAd if this is the case.
This is all speculation of course based on limited information.
You also need to provide more information than minimal log cut and pastes.
I do not think making a blanket "do not buy this router" thread is going to help your cause, as there are 100s of people on this forum who very sucessfully use that router, it is, the most recommended and most popular router on this forum in fact.
That said I understand your desperation on trying to get it to work (as it should) I think you should try starting again from fresh.
In view of this I'm going to try to invoke a few gods of the forum who
may be able to run through how to fully reset, update the firmware and set up the wireless for you, hopefully getting rid of your issues.
@L&LD @SomeWhereOverTheRainBow @ColinTaylor @Tech9 @thiggins, If you would be so kind as to look at this thread
https://www.snbforums.com/threads/rt-ax86u-disconnects-frequently.77815/page-2#post-753133 and offer your advice maybe you can get this guy up and running.
@pb9 please be patient you have some real expertise on this now.
Thanks
edit: Thanks Tim for merging.