Funny - there's a lot of talking about Vol de Nuit on various boards right now. Someone started a wave or something?
I'm not a sillage freak, so I'm more than satisfied with all my Guerlains' longevity, also Vol de Nuit. It doesn't last a longer or shorter time than any of the classic Guerlain EdT's. So perhaps I'm not the one to give my view to someone who likes monster-scents.
The EdT is more 'open', transparent and powdery than the extrait. I can also recommend the EdC which is even more open, very much herbal and inviting, in the same vein as Jicky EdC.