DIY speakers by Siegfried Linkwitz are unburdened by marketing concerns and are based on empirical evaluations and exceptional insights in the field of psychoacoustics. The engineering approach to various types of distortion and radiation patterns employed simply cannot be found elsewhere, commercially available, or otherwise. It's not that his designs are a bit better. They are a revelation. Interestingly the best implementation of your cookie cutter transducer on box design is found neither in commercially available consumer speaker lines nor DIY kits at Parts Express, but in a handful of professional Active studio monitors targeted at the recording industry. And those are a distant second.