A good GPS handheld unit is critical to borderline traverses. The whole idea is to walk the border in a line that matches the border itself, recording way points as a verification. These borderline walks are far from easy, especially on straight line borders that make no leeway for the topography or plant life and rivers. Some variations are inevitable but the idea is to stay on the borderline itself as accurately as possible and record some of the difficultieis in doing so. Here is a link to one of the best sites I've run into for analyizing GPS units.
GPS There are some others and hopefully readers will add their own comments on their own experiences with various models.
