I also get about 8 hours out of the batteries. This seems reasonable but it does mean you are running out of battery when coming into a harbor after a long day. This is a good reason to have two handsets or install the charging
station in the cockpit
station is very well designed. It mounts to something vertical (like the side of a helm
or inside of a coaming). The handset drops in and snaps out easily. There's a little red LED that shows it's charging. The idea of installing a switch is a good one. What I do instead is pop it out and put it in the drink holder when I figure it's fully charged.
Of course, I then have a problem of where to put the drink