Hi all,     We are new to Geocaching (1 week today) and are enjoying the fresh air and the challenge of finding the caches that have been hidden by fellow Geocachers.  We live in the UK and are looking at getting a handheld GPS Unit instead of using our mobile phones as we have heard that they are more reliable and the battery life is obviously a lot longer on the handheld units than a mobile phone.   Our question is:  Can you recommend a handheld GPS Unit for Geocaching?  Th