Among the many things that the worriers miss is that the amount of time an ETOPS 330 plane is likely to be in an area beyond ETOPS 240 or 207 is small. Further, propulsion difficulties that are not common to all engines (e.g., running out of fuel) generally appear when engines are at high or changing loads (e.g., on takeoff or in climb, not in cruise).
Thus, the situation one must be worrying about for ETOPS 330 is one in which the plane has taken off and cruised for at least 4 hours (i.e., to get beyond ETOPS 240 range) -- and then has a problem.
While anything is, of course, possible, the statistics show this situation to be highly unlikely. And note further, you are still not in the soup. You have one remaining good engine that must also go bad before the sh__ really hits the fan.
In my younger years I flew B707s, DC8s, B747s, DC10s, L1011s and A340s all of the time. But the safety record of B757s, B767s, A330s and B777s trumps them all. I, for one, am a statistician and decision analyst, and have no concerns about ETOPS. I do have great concerns about the driving safety of cabby who picks me up at the airport, though. Those guys really are dangerous.