I'm pretty happy with my Edge 810 now that I've gotten used to it. In the beginning I did experience some frustration. I got the whole package with heart rate monitor and speed/cadence, but since I purchased mine Garmin came out with the Edge Touring (and Edge Touring Pro after that) that sticks to the mapping features. As long as you're not after the fitness stuff, one of these could save you some cash.
The Edge 810 (and I assume the Edge Touring models also) can navigate to point of interest similar to the way an auto GPS does, but there are no verbal cues, only beeps. Typically, I don't use this feature because the unit doesn't really do very good at picking the best bicycle friendly choices. It is great for letting me know where I am on the map, though.