I have used these quite often lately and further to my previous review I have found the following...If you use them for rider to passenger, or bike to bike, they are great. But...if you pair the set to more than one other set, and try to swith between two sets they are virtually useless. You can only swith from one to the other if both sets are "off line". If wind noise is keeping either "line" open, or if the party's unit you are trying to swith to is in use by them, you get a busy signal. It will become very frustrating to use these units when paired to more than one unit and trying to switch between the two. I tried to find a phone number for Cardo to discuss with them, but no success.
I still like it for bluetooth and rider to passenger or bike to bike, but not both rider to passenger and bike to bike.