Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Buy the original releases

The real "early days" is every track on Zep's first four lps. Of course, every song (almost) on every Zep album is essential, so why waste your time with this? Every Zep album is important (well maybe "Coda" is stretching it), so there is no need for this. If you are curious about Led Zep and need an intro, start with "Good Times, Bad Times" and go from there. Amen.