"One of my top 5 moments in 30 years of D&D was in that adventure." - a player from my table.
Escape from Phlan is an odd beast. It is at the same time, an incredible adventure, and also a strangely disappointing finale. The first season gears up the players for a final encounter that is never supposed to happen. That being said, this module permits the choice to engage in that encounter if the characters choose to do so, and it's a doozie. As for the rest? Creative, interesting, vibrant, and a blast to DM. The players LOVED the grim and bleak tone of the module that made all of their choices feel important and large. At one point a player asked, rightly so, "Wait, so we don't actually have a plan for getting out?" I didn't even have to answer. Another player responded, "Exactly." And they charged forward with their task.
Admittedly, the final encounter that I allude to, my players did enter. It was a brash, unwise, choice, that I expected would end in a TPK. To my own surprise, they found a really incredible and creative way to circumvent a challenging piece of it, and came out triumphant. It was an incredible end to the season and the module. That night, they each felt like heroes. This module is good D&D at its core.