It must depend on the user. I have worn them daily since end of April and only ever notice when they're not on my head. I'll feel a vibration in my pocket and try to check glass. The first few times you wear them you may notice them in your peripheral vision but your brain quickly tunes them out. There is no obstruction of my view.

In my opinion, they are far safer to wear and use for the purpose of navigation than a phone or mounted GPS. They give me the necessary information quickly and don't require me to adjust my vision off the road.