This was a fun adventure, possibly a bit difficult, especially if the demon patrol doubles up with the guard hezrou.
I run 3-hour sessions, so had to remove an encounter to account for that, but I would say this can be run quite easily in 4 hours.
Overall I would definitely recommend, the boss at the end is great fun to fight. :)
P.S. Also loved the references to previous editions!
[5 of 5 Stars!]