Rodriguez Toucan tandem, Rodriguez Rainer Lite sport/touring
The Garmin 305 is designed to tell you where you've been, not where you're going. It's a training tool that allows you to analyze your ride afterwards. It is not designed for direction finding and does not have the capability to give you turn-by-turn directions.
Map your directions in a website like "Mapmyride.com"- download to the file to your Edge and that'll give you a turn by turn path. Except for the mapping software thats included, its worth having one. Especially since the costs are coming down since the newer models are coming out.