ETOPs can be quantified in minutes, I believe. Such as ETOPs 180.
It's possible that the same aircraft type with different engines or even operators might not qualify for the same ETOPs rating.
Not sure whether BA's 777 and Air France's A330 have the same ETOPs rating. I do believe that Air France's 777-300 rating may have suffered after several in-flight shutdowns in the last year. (possible it is now back up and running).