I just bought the self-centering drill jig from Jim at OMC. It is built strong and heavy! I've only used it a half dozen times or so, but so far I am impressed. It has been very easy to work with, and the holes have lined up perfectly so far (knock on wood). Leaps and bounds better than the Bingham's jig. And the time and frustration saved so far, has been worth the investment. And it's built specifically for bow making. No having to chase a hole with the correct size drill.