How many seasons do those things last?
I thought about buying some, but the i felt like the batteries would die over summer, and I'd be lucky to get more than one season out of them.
The Chips Helmet Audio has lasted me over 8 seasons and going strong. I don't maintain the batteries (I believe they should be stored with a 75% charge during off season) and still get enoigh charge for 2 full days of riding.