I've had the Sana SMH10 for approx. three years now and love it. I have friends who purchased UClear only to learn they hated it and was about to chuck it during a ride out of frustration. I recommended the Sana, and they love it. I listen to music through them, intercom is clear, you can speak group talk with up to three other people in your intercom group at the same time. It's very convenient being able to talk to your friends to let them know you need gas, restroom stop, or where to go for lunch. And its funny how those who don't have communicators don't have a say... they just follow you.
When I'm answering a call, the other party can't really tell I'm riding 80 mph on the freeway. They just hear a little background noise. It's also great to be able to voice dial someone while you're riding to let them know you're on your way or running late. If your phone is capable... you can also do voice activated texting.
The dual set Sena SMH10 have generally been priced around $230-250 on Amazon. The 20C is the newest model that has more features... able to add up to 10 com systems into your group.
As for the speakers... the Sena speakers are good. They are also thin so they can easily be placed in any helmet with ear/speaker pockets. I however wanted more volume and bass, so I spliced and soldered a pair of high fidelity J&M speakers (from my old CB headset) to the Sana base system. The sound is wayyyy better. However, the speakers are at least two or three times thicker than the Senas, so I had to carve out some foam out from the helmet's speaker pockets. When I spliced the speaker wires, the J&M were no problem... the speaker wires were pretty thick, easy to work with. However, the speaker wires for the Sana were soooo fragile, so you have to be very careful when you strip the wire... because there are only three or four strands inside each of the cords. The strands are as thick as hair, so give yourself plenty of cord length.