Catrin:

Sounds like you are happy with your mirror choice. FWIW, I have the Take a Look mirror and I love it. I use it mounted on glasses. There is a learning curve -- it's weird at first, but now it's second nature.

Using a mirror and learning to look behind you are not mutually exclusive. You can do both (and you should). The mirror is great for very, very crowded urban situations which is where I spend most of my time.