I was first introduced to Mo dao Zu Shi through the anime, which is what lead me to watch The Untamed (and also read the original novel).
Having seen the story retold in three different mediums (all of which were enjoyable), I can say to anyone who has either read the novel and/or watched the anime and whom is considering this series, that I believe you will be able to enjoy the TV series just as much.
The acting from the leads and supporting cast was well done. Wang Yibo particularly did a wonderful job in his portrayal of Lan Wangji which is quite a difficult character to recreate. Xiao Zhan also did an amazing job with Wei Wuxian, in both depicting the happy and tragic aspects of his story.
Furthermore, considering the ban China has against homosexual relationships shown onscreen, I highly commend the writers/directors and actors for being able to bring across the depth of love that Lan Zhan and Wei Ying have even with the restrictions placed upon them.
The music was also incredible.
Personally what I loved the most about The Untamed is the depth of character, the thought provoking and morally challenging dynamic it has, as well as the depiction of relationships between lovers, family and friends.

As for any critiques, the CGI while not the worst I have ever come across is not the most realistic of portrayals at times (although that could just be because I am not so familiar with the genres style of depiction in Chinese filmography).
Furthermore, while I had already known of the time skips which occur in the story, I have read on several occasions that for watchers who have only seen The Untamed, that the time skip which occurs in the show was not clear enough and some viewers were left confused.

Regardless, I loved The Untamed and have personally watched the series three times already. I can definitely see myself re-watching the series again some time in the future.