I bought this album after the other four because half the tracks have vocals and I really prefer the instrumental pieces... But I finally decided my collection was incomplete without The Nth º, Alive and Contact.
Alive really stands out to me as a kind of energetic celebration. It's always easy to listen to, no matter the context, and it's filled with all those lovely unique breaks that I'd become so fond of in the later works.
Favorite track: Alive.