Depends on which 'over the ear' headphones you have. If they have active noise cancelling, chances are the over the ear will be better at drowning out noise on a plane. That being said, the way the Buds nestle in your ear already make it for a sealed experience and they do drown out a lot of noise. Whether or not that will be enough for you, it's up to personal preference. I had no issues flying with mine and a pair of Jabra 65t, but if I don't activate audio pass-through, I could hear, albeit faintly, when the seat belt sign came on/off and conversations around me (not too loud) if I wasn't playing any audio. If I played audio, however, I could barely hear anything other than my music.
The main problem I see with the Buds is battery life. Over the ear ones are usually rated for 10+ hours, while the buds will last you 5 to 6. Unless you stop and charge mid-flight, they won't last a very long trip.