I recently purchased Legend of a Band along with the longer and more expensive Classic Artists 3-DVD set.  I must say while LOAB doesn't show as much footage as CA, it does seem to tell the story much clearer and without a lot of the superfulous interviews of people that most of us have never heard of anyway.  I am a huge John Lodge fan and the segment of him at the  site of The Isle of Wight Festival was fantastic and that alone was well worth the price of the DVD! I highly recommend this to any MB fan.