I have never watched the old version, but I am watching this version and I think it is decent.
I think Chompoo's portrayal of Sai is off making the character not very likable, and Mew Nittha's portrayal of Looksorn makes the character very weak and bland but I am not sure if her character is supposed to be that way. However, in general, the plot, pace, and complex relationships make the lakorn interesting enough in my opinion.
I am not sure on the accuracy of this, but I read somewhere that the old version differed in certain areas to the novel. They said Sai's character in the novel was more malevolent than in the old lakorn version, trying to break up many couples that society thought were suitable because of her hurt past, however her manipulative ways were more subtle and high class and not outright like chompoo's portrayal in this version.
Also they said in the novel, it was clear that the one Sai loved was Buri not Charles, she only had a flirting, more than friend but less than boyfriend relationship with Charles. However in the previous lakorn version it was unclear whether she loved Charles or Buri.
So perhaps this new version may disappoint people who watched the old version because of the differences, but it could just be a different interpretation from the novel. Chompoo's portrayal of the character leaves a lot to be desired because I heard the last version was very memorable. But I still think people should give this version a chance. This thread has been very quiet since the lakorn started airing.