It's from a different article, but the author gave an interview to hackaday and gave a comparison there. https://hackaday.com/2023/10/31/black-4-0-is-the-new-ultrabl...

> “Black 4.0 absorbs an astonishing 99.95% of visible light which is about as close to full light absorption as you’ll ever get in a paint,” said Semple. He notes this outperforms Vantablack’s S-Vis spray on product which only achieves 99.8%, as did his previous Black 3.0 paint.