You now better since you have it , was not aware of the described configiration to achive distance have to admit, the rumor here supports companies claims but as have no personal opinion might as well take your word for it and stay away fm it, have to admit was going to get it , love its remote control.
In any case am currently satisfied with my system 5 bmw helmets , old but still me and my pillion after 8 years enjoy them , up to now only a pair of batteries was needed.
The interphone 4 on the other hand (bought for 240£ , back in 2010 fm Nippy Normans with a coupon of 10% discount offered to the old site members) now is retired sitting in my garage in its box cause started to pressent varius issues, cable connections, microphones, earphones, all at some point needed replacement.
If someone needs some parts huppy to give them.