I bought a Sena smh10 for my Bell Mag 9 I didn't know you had to get the different inside piece. I haven't yet. Does it make that much of a difference. I do know that I quit using my Garmin gps. Because with the Sena unit it will talk through the speakers in the helmet. I like that. I mainly got it to play music & in case my kids needed to get ahold of me.