My experience with handhelds is that most of the places you think they'll be useful in (remote areas with no cellphone service) they don't work. Why? Because of terrain. Most portable communicators are just not that powerful, and things like woods, hills, and mountains shrink their already limited range to something almost useless.
I also can't see wanting to wear a headset all the time while biking. Just... no. The amazon description says: "Filter out unwanted noise with Cut-the-Noise technology." That seems like a terrible idea. There's a reason I don't wear noise canceling headphones while cycling, and it's because a lack of situational awareness might see me squished like a bug under a motor vehicle.
I could see these being somewhat useful in a couple different scenarios: 1, a cyclist who wants to communicate with their sag vehicle more conveniently. 2, Cycle tour guides who want to talk to each other while they're at the front and the back of a tour group. There are probably other scenarios, but I can't see small group cycle touring as one of them. Wearing them just so that you can chat all day while riding a bike isn't very appealing either - as anyone who has traveled for any time in a small group knows, if anything you get tired of having to talk to each other after a while of spending all day, day after day, together.