So I ran this tonight with a party of 5 people, A lvl 1 Bard, a lvl 1 Cleric, a lvl 3 Ranger, a lvl 3 Rogue, and a lvl 3 Sorcerer.
The story is great, you're infiltrating an enemy organization and framing them for attacking another enemy organization to the benefit of the Pathfinders. Awesome stuff. The module has you running all over Riddleport and wheeling and dealing with some of the more important folks in the town. It's mostly skill checks here.
After that, you head down into a cult lair under the city. Unfortunately, this is a lot of the party moving from empty room to empty room trying to figure out a way to sabotage the place...which leads us to the bad
There are two encounters in here which are just absolutely brutal for 1st level characters. The 1st is a basilisk hidden behind a illusory wall which disappears when the PC's trigger a trap. The basilisk is behind iron bars that the PC's have to break down to get to it, all the while it gazes at them. Then, once they get inside (which they will likely have to because someone will fail the save and be turned to stone, so they'll need it's blood), it has 38 HP, +8 to hit with a bite, and does 1d8 +2. Ouch.
But no, that's not the worst. The worst is a golem in the 2nd to last room. There is no way to avoid this fight. If the PC's sabotage the lair (Their mission), it activates. If the PC's enter the last room without unholy symbols of the god, it activates. If the PC's try to damage it or mess with it (A faction mission makes this a likelyhood), it activates.
This this has 47 HP, has 2 slams at a +10 to hit and does 1d8 + 5 damage. That's right, it averages about 9 damage an attack, 13 max. Against level one characters, this fight is just brutal. Did I mention that it resists 5 Fire, Ice and Electricity? Oh, and it has light fortification, so it has a 25% chance to negate crits.
This thing quickly put the ranger down, and I had at one point three characters healing the ranger with wands just to keep pace with the damage and it just wasn't enough. They only survived because of a clever kiting strategy that allowed them regroup, and by that point two PCs were down and bleeding out. Not to mention that this fight took a long time. At LEAST an hour.
I'm all for a challenge, but that was simply too much. Had it been a party of 1st level characters, I guarantee I would I have wiped them out.
Overall, I like the story, but the challenges at the end are FAR too difficult for a 1st level party. A dungeon with 2 APL + 3 encounters is too much. If you are running with experienced players in the 2-3 level range, this is going to be a challenging scenario. If you're running with all 1st levels, you are probably going to TPK them.