Delightful. The vocal harmonies with the horn, the melodies: it's been said, so I won't go on, but wonderful.
Nitpick: I think the spoken word sections (which I love) may come in slightly too loud, especially at around 4:40.
It is a bit long as an active listen, but it's obviously more of a pleasantly ambient background type of song, so I wouldn't worry overmuch.
A little bass definitely wouldn't hurt.