There were two versions of Desolation Boulevard. The UK version, released in November of 1974, came out first and contained the original recording of their massive Glam rock hit "Fox On the Run"(UK#1/US#5). Yes, there were also two different versions of "Fox on the Run". The American version, released the following Summer, was a compilation of the UK Desolation Boulevard and predecessor Sweet Fanny Adams and broke the band in the America just as the UK was losing interest. Unless you're a fan of very long drum solos ( "The Man With the Golden Arm"), get the US version.
Can you think of another classic example where it would have made sense to combine two albums into one classic?