as in anny battery
powereddevice the problem is the battery andbattery charging
circuit, NAsa and tactick are the worse, seems that the new garmin is a litle bit better but there are still new, i presume that in 4-5years will have a high rate of faulty units... not always changing the battery solves the problem and the repair out of waranty is realy expensive.
Just think about the mobile phones: how long the battery will serve you... not more than a couple of years... I totaly advice against anny wireless solutions for the mastheads...