We started using these last year in my group, but I only have about a week of experience with it: https://www.motocomm.com/products.ph...oductCatID=163
Things I like:
1. It uses a separate GMRS radio, so I can use my radios for other stuff in the off season (hiking, boating, etc), rather than having the radio tied to only my helmet. We can also have an unlimited number of riders in the group since it's just a common radio frequency.
2. It has a separate PTT for the rear passenger, so the wife can take part in the sled-to-sled conversation (ok, SHE likes that part)
3. Longer range than the bluetooth ones.
4. It hooks up to my MP3 player and will automatically reduce the music volume for intercom or radio transmissions.
Things I don't like:
1. Lots of wires
2. It's taken some tweaking with the mic and speaker placement to get the volume just right (foam blocks behind each, to bring them closer to my ears and mouth).
I use my Nuvi as my MP3 player, and it hooks up to the comm unit. It will also play the Nuvi's turn-by-turn if you want. I turn that feature off where I ride though.