CyanogenMod 13 is based on Android 6.0.1 Marshmallow which is pretty much the latest version of Android right now, so users won’t have to worry about their phone not being up to date if they decide to go with a ROM. That being said, there are some drawbacks to using CM13 over OxygenOS.
One of those drawbacks is that the handset’s Dash Charge feature is not supported in CM13, meaning that if you were hoping for rapid charging, CM13 won’t be bringing that feature to your phone. However the developers have stated that they will be releasing it soon, but for now if you plan to use the nightly build, it won’t be there.
It also seems the camera quality has gone down as the processing software used in OxygenOS is no longer there, so unless the team at Cyanogen can figure out how to bring that feature back, lower camera quality is something you’ll have to deal with. However if you’re fine with this, then head on over to the CyanogenMod website for the download.