Since Traffic's debut album Mr. Fantasy has been issued in different configurations over the years, a history of those differences is in order. In 1967, the British record industry considered albums and singles separate entities; thus, Mr. Fantasy did not contain the group's three previous Top Ten U.K. hits. Just as the album was being released in the U.K., Traffic split from Dave Mason. The album was changed drastically for U.S. release, both because American custom was that singles ought to appear on albums, and because the group sought to diminish Mason's presence; on the first pressing only, the title was changed to Heaven Is in Your Mind. In 2000, Island reissued Mr. Fantasy in its mono mix with the U.K. song list and five mono singles sides as bonus tracks; it also released Heaven Is in Your Mind, the American lineup in stereo with four bonus tracks. Naturally, the mono sound is punchier and more compressed, but it isn't ideal for the album, because Traffic was fashioned as an unusual rock band. Steve Winwood's primary instrument was organ, though he also played guitar; Chris Wood was a reed player, spending most of his time on flute; Mason played guitar, but he was also known to pick up the sitar, among other instruments. As such a mixture suggests, the band's musical approach was eclectic, combining their background in British pop with a taste for the comic and dance-hall styles of Sgt. Pepper, Indian music, and blues-rock jamming. Songs in the last category have proven the most distinctive and long-lasting, but Mason's more pop-oriented contributions remain winning, as do more light-hearted efforts. Interest in the mono mix is likely to be restricted to longtime fans; anyone wishing to hear Traffic's first album for the first time is directed to Heaven Is in Your Mind.