So like the title says it's an important questions for those deciding between r710 and r720. It's advertised that r720 supports 160Mhz and it's the only reason to buy it over r710. Without 160MHz the 2.5G link on the r720 is useless. In fact r710 is the better choice because it draws substantially less power in a typical low load scenario.
I just saw the release notes for 200.9. It states "160 MHz Channelization | Introduces 160 MHz channelization support for Wi-Fi 6 APs." I have 3 R720 APs in a test environment on 200.9. I still cannot set 80+80 or 160 Mhz from the GUI. Perhaps Ruckus could comment.