I purchased the Cardo Scala Rider G9 PowerSet approx. a year ago and have loved them since day one.
My wife and I both ride...she rides a Harley Softail Deluxe and I ride a Harley Road Glide. Whether we use them for bike to bike communication or rider to passenger on the rare occasion that we ride two up, it works flawlessly. I particularly like the fact that we can communicate bike to bike over such a long distance, especially if we get separated in traffic, I can still talk to her and keep track of where she is.
On flat terrain on the freeway we have been able to maintain communications at a distance of 1.15 miles apart which is a great thing. Of course that diminishes when you lose line of sight but still plenty good enough to maintain communication over a very respectable distance. Definitely within the range of separation that we typically ever get into.
She loves the built in FM radio feature since she doesn't have music on her bike. I also frequently lead rides on group rides and it is great being able to communicate with the guy running sweep....it adds a HUGE safety cushion that way. I can't say enough about it. The only drawback is in the winter time when you're wearing much thicker gloves I find it a bit difficult to sometimes find the right button.
The Bluetooth feature is fantastic. I have my iPhone 5 paired to my Garmin GPS and have my GPS paired to the Scala. WOW. I can clearly hear the GPS voice commands at any speed and I can make and receive phone calls as easily as I can at home.
The call clarity on the phone is phenomenal. I consistently take calls while going down the freeway and even at speeds of 70-75 mph the people on the other end of the line have no clue I'm on a motorcycle unless I tell them and then if I do, they are shocked.
All in all, it is a great product and I would recommend it to anyone for intercom between rider and passenger or for bike to bike communications. You won't be disappointed.