As with most polls the options are very limiting and cannot cover many set-ups. For example we carry hubbnies Notebook for him to be able to still run his company while afloat. This does have chart plotting on it, but is rarely switched on. So I have discounted it. We carry two basic Hand GPS machines to sit in reserve should they be needed. Both of those and the main plotter have 12v supply cables so can run of the portable emergency power pack. The hh's of course also can use aa batterys. We looked at aa battery life and felt that the power pack was a good idea. Portable, reasonable life which is far longer than aa's.
-------------------- Some of us Ladies may surprise you.... Wife of Refueler