It really depends on what 0.1%.
If the car fails to detect one in a thousand cars in front of you, or one in a thousand corners, I can see that being highly dangerous.
Let's say you change lane 5 times while commuting. That's 50 times per week. Now, are you going to pay attention well enough that you catch it twice a year just before it pulls out right into another car?
Perhaps likening it to having another person driving you would be good. If you were given a perfect chauffeur, except with the knowledge that they'll drive straight through one in a thousand red lights with no warning, are you confident you'll catch them?
