I noticed and chatted to several club members recently that have purchased new Garmins. As a source of information and if you want to find out more about Garmin / GPS and mapping for rides see the link on Audax UK web site;
http://www.aukadia.net/gps/
There are other posts within the message board, to search for other information using an appropriate search terms such as GPS will reveal the other postings.
New Garmin Users
Moderators: Philip Whiteman, Andy Terry
New Garmin Users
Si Walker
Beacon Roads Cycling Club
Beacon Roads Cycling Club