We just finished this module with my group. All seasoned role-players, but some newer to Pathfinder, and esp Society play (this doesn't need to be done as a Society module).
We had a mix of 1st and 2nd level characters, and there were some things that were really tough for them. (no real cleric, btw. Ugh!)
The characters are not really supposed to go back to town - and there isn't really a need for them to do so, as stated by others.
There were a couple rooms that were easily designated as safe rooms if they needed a rest.
It took us 3 sessions of 4-5 hours each, and I drew the maps as we went. If you have them ready ahead of time or use the flip-mat, that should make things easier.
Also... bit of a SPOILER...
The group got a little confused/frustrated that this whole thing was not exactly what they were 'told to do'. They were wondering why so many other groups were sent here before them. It made them a hard to handle at times - but then again, that might just be how my friends are. =]
Good luck, and have fun!