Review on Precision Stainless Woodworking Protractor for Accurate Degree Measurement by Ross Bagby

I bought this because it's a great concept but it's not executed accurately. The measured angle is wrong. In the middle of the ruler, not at the edge, the angle is exact. The protractor is made of good material, runs smoothly and is easy to read, but if it doesn't measure correctly, what's the point? The concept needs to be improved.