I bought this item about two years ago. It completely failed after six months. It took weeks to get hold of customer services but to be fair the item was replaced within a week.
But it wont update via the cd included and the battery life is worse than my iphone, infact it makes my iphones battery look like a nuclear power generator, its useless.
It also freezes from time to time and has even frozen for about 2 hours once literally leaving me in the woods.
All in all the only recommendation I can give is to spend your money elsewhere