Hello all - signed up a few days ago after finding this thread (googling for problems with the router).
Same experience as many. On the 2050 firmware I used the feedback facility to report issues, uploading the dsl log, and went through several changes of settings as per the advice, but still kept getting dsl disconnects several times per day. Went bak to the Openreach modem (using this as router only) and everything was rock solid for a week. The speeds (Infinity 1) which had dropped during all the disruption got back to about 37/7 (as good as I'd ever had).
Tried this latest firmware and got disconnects within 2 hours. With default settings the speeds jumped up to about 40/7.5, too high probably. There may be some magic set of settings, but finding/trying them messes everything up so much its just not worth it. Have gone back to the OpenReach modem and will sit tight for a bit.
As posted above the routing side is fine, WiFi strength is improved, but the modem.....oh dear. I've reported to Asus, and llooked on their forum but not expecting too much. The "n" version seems to have the same issues, maybe using the same hardware/firmware.
Got a very expensive router (minus one ethernet port) at the moment. Would send it back if I could face going through all the aggro again but I can't!
I'm getting the same problems with disconnections between 1 and 5 a day mostly at night. I have also changed 2 or 3 settings on the advice of Asus but roughly the same and the newest firmware had no effect.
I am holding out for a while longer then will go the same route as you with the Openreach modem.