Hello all. Just got 2 Hafny Bar End Bike Mirrors from Amazon. Only had them for a day, but so far they have been working great. They fit perfectly in the end of the handlebars. So much better than twisting back to take a quick peek. I put them on both sides, and I think they are both needed, at least how I have them mounted. Depending on conditions, I will see traffic in either the left or right mirror. The reflective part is metal, so no issues with glass breaking. I've not noticed any blurry vibrations going on either.