I will make this review short and to the point. If you are new to hide, this is an excellent single to start with. It displays two very distinct sides of hide's music. His heavy metal side with "Doubt", and his pop/rock 'n' roll side with "50% & 50%". I bought it before I bought hide's Best cd. This is not an easy to find cd. I would recommend buying hide's Best, only because the production is better, and it contains both songs, with a very slightly different "Doubt". Hide fans will want the single because of its rarity here in the states, and that is what loyal fans do.