It's not only difficult - it's down right impossible! It's just the same as asking what's my favourite album - I think it might be an old fashioned legacy of the days of vinyl - but I put a cd on and listen to the whole thing, not just a couple of tracks, the other thing is I rotate through all the albums so I've listened to everything equally - I love the whole cannon of Oteps work - every piece is as meaningful to me as any other.