As a big Led Zeppelin fan, I was eager to get these remasters of Led Zeppelin mainly for the bonus material. However, if you already have the complete set from previously, this release is not necessary for the casual fan. The demos are interesting to listen to, but after one or two times, I can't imagine repeated listens like the album tracks. I couldn't tell a huge difference aurally between the two masters (but I am not an audio expert). So unless you are a die-hard fan, you may want to skip this one.