The problem with both rider and pillion listening to say music from one mp3 player or phone is that the phone/mp3/GPS etc will only connect to one bluetooth device at a time, the SMH5 will connect to up to 4 devices at the same time so you can have your phone connected to your GPS and then connected to the SMH5, which is the best way or you can connect your GPS and the phone seperatlely to the SMH5.
You can connect to your phone and the misses can connect to here own phone and MP3 and still be connected to you as an intercom. The SMH 10 is probably the best bluetooth intercom on the market at the moment for the money I have to say I maybe a bit bias as i do sell Sena intercoms but I do also sell the Interphone intercoms and Scarla Rider as well, I think the SMH5 is the best for the money if you only want rider to pillion and GPS/phone etc and the ability to use it as a bluetooth intercom for bike to bike occasionally, if you want to use it for bike to bike most of the time then I suggest the SMH10
Cliff