After lurking for awhile I decided to post my issue. I just recently bought an Asus RT-AC5300 and set everything up. One of the first things it asked me was to upgrade to the latest firmware: 3.0.0.4.380.7266 which went fine. I used the router the entire day and shortly after setting everything up all my wireless SSIDs disappeared and I lost connectivity on LAN for about 15 seconds. It came back up just fine after this 15 seconds and it worked the rest of the evening.
The next day...
RT-AC5300 Bricked Issue w/ connectivity dropping randomly?!?!
The next day...
RT-AC5300 Bricked Issue w/ connectivity dropping randomly?!?!