My route covers about 16 miles. The upper 8 miles is gravel, dirt, sand, occassional ruts. I tend to ride on the right side but will move all over the trail to stay on a firmer surface. The first 5 miles is usually not very busy and it would be easy to get surprised by another cyclist aproaching from the rear. Getting surprised at 14 mph on gravel could lead to a problem. It's here where I have the most concern about being warned since its easy to get lulled into the ride.

The next three miles is full of joggers and dog walkers. Some oblivious due to iPods, but most will move right and wave and/or reel in their dogs when I announce my pressence.

The rest of the trip in on paved trail, generally wide. There tend to be other bikes moving in both directions here. It's easier to keep a straight line here so getting passed is not as big an issue, barring something on the trail in front of me. I guess I don't worry about other rider's courtesy here since its busiest enough its more like being on the road.

I think my next purchase will be a bell, see what kind of reaction that brings.