Second half, just because of "V" , best of band´s output, best progressive metal album ever and one of the best albums ever in metal and progressive music. But actually my choice would be the entire discography rather than a half
Tough question, because the middle four albums are my favorite but if it's Divine Wings of Tragedy - Twilight in Olympus vs V - The Odyssey, I'd have to choose the latter two, but only because I've overplayed Divine Wings of Tragedy just a bit.