I use the SMH10R, which is a slim version of the Sena SMH10. Excellent unit, very easily operated whilst gloved, killer battery life, excellent clarity for bike to bike or helmet to helmet. I can take calls via Bluetooth or directions from my GPS. Has voice call, voice activated answer, etc. etc. For the price, the Sena is a great choice. Also, has universal communication capability with the other major manufacturers... definitely find that feature, whatever you decide to buy.