I have had the Sena SMH10 for probably going on 6 years now. Original batteries, but I don't ride every day either.
Have had zero problems with mine, my wife had issues with the music coming back after we talked to each other, but I did firmware updates and that took care of that problem.
That is one of the great things about them as well, the ability to get firmware updates. The Sena is now able to do way more than it used to, since I have updated it.
A friend of mine tried to avoid getting the Sena and went through 3 different brands before finally getting the Sena. I don't know which ones he tried except for the Cycle Gear version, but he had problems with all of them.