I don’t think he is biased. There would be no reason. As far as I know, from this and another forum, @dbb is an amateur music lover like me and you. He is not a dealer. He bought the Musetec and the Holo May with his own money, and after the review he was satisfied to keep the Musetec and sold the May. I do identify with him as his passion is for classical music and his listening references are live unamplified concerts. There isn’t a better reference IMO. So that was the basis of the review.
I don’t think it is fair to say that the conclusion was, "The May didn’t hold up to the Musetec 005." As I read what he wrote, he found them to be very similar notwithstanding their very different architectures. He pointed out their very small differences. Being that close in SQ performance, he decided to keep the one costing less money.