My group really enjoyed this as a side adventure when only three of them (5th level) could get together to play. Great mix of roleplay and combat, mystery well-constructed allowing several paths so that the players can make the adventure their own and every PC should get a chance to shine. Well-written and well-organised making it easy to pick up and run, and to customise to my own setting.
EDIT: have now run this adventure a second time and it was just as awesome. The players again loved the construction of the mystery and felt really rewarded from their roleplaying and skill checks, and the product is so well put together that as DM it was a pleasure to run it and roleplay the NPCs.
[5 of 5 Stars!]