Have had this product for more than 1 year. I'm an avid cyclist, 3 times a week, over 3,000 miles a year (OK, I'm retired) During the summer most of my cycling is on country roads so it's imperative that I see what's coming before I hear it. It works well once you get used to it. First you must set it up on your helmet. With some of today's designs this takes some thought, but stick with it (no pun intended). Then you must position it so it doesn't block your forward vision. Practice around the house or walking outdoors until you feel comfortable. The mirror arm is quite flexible & strong so it's easy to move. The oval shape gives a large view & the mirror design increases the depth of field to make it easy to see the approaching objects.As well the mirror itself swivels making it adjustable for anyone. If you have to move it to another helmet I found that several layers of 2 sided thick carpet tape worked just fine to secure the base. The mirror which snaps on a little ball joint at the end of the arm became sloppy so I wrapped a small piece of painter's tape around it. It's quite strong though as I found out when I took a tumble off my mountain bike. I cracked my helmet & ribs but the mirror stayed on in one piece. Would highly recommend this safety device to any cyclist whether you bike on roads or just a neighborhood trail. I gave it 4 instead of 5 stars as I feel you should be able to order additional arms and or mirrors as needed.