I quite enjoyed DM'ing this adventure.
For most of the session, I was watched by a friend who had to write a report on a certain activity (he had chosen D&D, and I had invited him to watch my game), so I made very good use of the interesting roleplay parts of this adventure to give everyone a good time.
My favourite part was probably to find a performer role for all characters present. For example, a paladin with a Belt of Fire Giant Strength was Da Strong Russian Man ! They were certainly a nice attraction for the Red Plumes.
It was quite fun, during the sneak-around part, to have that one particular Red Plume just following them around like a true groupie.
Going down the river was perhaps trivialized by a Water Walk casting, but still interesting with the mystieries of finding the lost faction agent's tracks.
I was happy that my characters took time to discuss with the big frog, so that they would have an ally in the end fight. Said fight ended when the big frog crushed the succubuses under his fat belly, then started eating them.
Overall, a nice adventure, with nice roleplay incensitves.
[4 of 5 Stars!]