I recently purchased and mounted the Quick Scans on the stock wind screen and have been amazed at the increased situational awareness that they have given me. I have them mounted close to the top of the screen and are above the BMW mirrors that are on the end of the handlebars. They do not require that I shift my focus downward and give me a total view of blind spot traffic.The mirrors appear to be top quality and were easy to install.
I made black vinyl inserts to cover the stock bike mirrors as I don't use them any longer and there was too much mirror. I had one problem. I cleaned the screen 4 times with denatured alcohol and lighter fluid and still after several weeks, one of the adhesive mounting pads started to loosen. I therefore, secured the mounting pads with a small machine screw thru the base pads. This did require drilling through the screen, but I am not planning on ever removing the mirrors and I do not want one of the mirrors coming loose at high speeds.
Also, I purchased additional bases for a second larger (Winter) wind screen. If you should buy these mirrors and have more than one screen, buy the additional bases when you order the mirrors as they are only $18.95 extra.