Quantity wise you get 5 CDs with 20 tracks on each one. Quality wise, I'd say at least half of the tracks would never make it into my top 250 all time rock tracks. I took this along for the long 18 hour drive across Europe and played each CD at least twice but the second time round I found myself simply flicking through tracks. I was disappointed but I suppose if I had the time, I could download all five CDs and then make up one list of the best 20 from these 100. I'm sure there are much better compilations available.