I got to play the series in high tier with 4 player adjustment (hard mode for some). I thought the story seemed disjointed between the scenarios. Part 1 is a story about the Sun Orchid Elixir and Pashow while the others deal with the Aspis. It didn't feel like it transitioned well.
I thought the first 2 encounters could use some work mechanically but the final one was very cool.
Unfortunately we played as part of convention and finished the entire series in 14hrs. I think a bit more time would have made everything feel less rushed and given time to explore more role play and combat too. I think the ideal is giving each part probably 5-6 hours.
I went into this game as a level 9 character expecting the hardest scenario I had ever played so far and this game did not disappoint. For 4 people in hard mode this game is extremely challenging even for a powerful party.
Be sure to have plenty of time when running this game. We didn't have time for the optional encounter and still ran about 6 hours.
5/5 Would play again. If more scenarios were like this I would be very happy.