Recently completed this while we had fun playing it the campaign was rife with WTF moments that were either annoying or discouraging.
As with the rest of the Serpents Skull Path The story line is something of a sand box albeit with a very specific point A to point B path that you have to follow.
The story line is predicated on the idea that your hired by a group in order to race to a curtain location before competing explorer groups... you would expect such a race to include several paths (short and dangerous vs long and safe), and reoccurring enemies (opposing groups hot on your heels and efforts made to confound each other),
The path has little to none of that. instead it is essentially a straight line from point A to point B with a spattering of random encounters every few days. a group of paladins walking in plate armor will travel at about the same speed as rangers on horse back and the path does not seem to provide any alternate routs or methods.
Granted all of the above are modifiable by the GM. I mean... a good GM can allow the players to take alternate routs and just build new encounters for the alternate routs... but isnt avoiding that work specifically why they buy these APs?
Lastly when you reach the end of the campaign you find that the people who hired you may actually beat you to the goal which makes you wonder why they hired you at all.
The campaign has loads of potential... but only if the GM knows how to enhance what the campaign gives and for this reason I give it only 2 stars because why buy it if I have to do all the work anyway.