Here in the United States, we don’t have access to Oppo phones. We do have access to OnePlus phones, though. Over in Europe, however, most citizens have access to both OnePlus and Oppo phones.
In Germany, unfortunately, that’s no longer the case. An ongoing patent lawsuit from Nokia (the Finnish equipment supplier, not HMD Global, which owns the Nokia smartphone brand) essentially bans Oppo and OnePlus Germany sales (via WinFuture).