Just reporting that I upgraded my WNDRMACv2 and WNDR3700v1 units to version 1.10.0 from 1.9.x from September 18, 2017. Did not preserve the settings. On the WNDRMACv2, I tested DDNS, OpenVPN, AdBlock Plugin, USB Camera, QOS w/ACC and WIFI (Both 2.4Ghz and 5Ghz). All seems to be functioning great!. On the WNDR3700v1, I tested USB Printing, it functions great as well. I also have 2 vlans (guest network completely segragated from regular network with internet only access) and vlan tagging setup between these 2 units and it is functioning great as well.
The only strange anomaly is that the WNDRMACv2 seems to always report an idle of around 0.72. https://imgur.com/F8XZen4
I've tried turning off openvpn, AdBlock plugin, QOS w/ACC, WIFI, and turning off Bandwidth monitoring through SSH and the idle usage never goes below 0.69. I've reflashed the firmware and it still shows the same usage even after a couple of factory defaulting. I experienced the same issue with the 1.9.x from September 18, 2017 as well. I don't experience any slow downs on the network, everything seems to be snappy with the web interface. When I SSH into the unit and do a top command, I see know excessive usage in memory or processor. Go figure.