I became aware of this product through the quickstart rules, although I have since learned there was a KS in 2017, and was awaiting the full rulebook being a fan of wuxia and finding the premise of playing an immortal companion to a questing monk interesting. The card draw system is simple to learn and adapted to the highly narrative concept of the game, but luck plays a great part in the outcome of any action, so using save cards and/or assist from your companions is required if you don't want to fail at something important. The character creation process with its story-like development and challenges is a fun way to set the stage for the campaign, but immediately underline the weakness of the product as is: the lack of sufficient examples and background information.
Your immortal is supposed to choose a Yin and a Yang Attitude, which is central to the game mechanic, and have some magical powers and items to help in his adventures. Yet, aside from 13 pairs of basic Attitudes, 14 Weaknesses, the 8 pregens and limited random choices (one per card suit and joker per origin for skills, story challenges and magic items (which may very well mean that a randomly-based party of four might end up with a few identical traits/background), you are left on your own to decide what they are. Same thing with only 5 broad realms basically described (Western & Eastern Heavens, Four Oceans, Earth and the Ten Courts of Hell) with 3 or 4 possible NPCs each. No map of the Tang China setting either. Maybe worst, aside from the 2 complete adventures provided, only 8 adventures seeds are given to provide some ideas of what this Journey to the West campaign could actually be like. You do get rules to play mortal martial artists instead of immortals though, but I feel that the option somehow changes the "celestial" scope of the game.
I get that some of the interesting sounding material in the KS, like the Ministry of Thunder adventures and the Golden Register of 101 Immortals and Demons aren't out yet (and may take a while to be), but the aforementioned are essential elements IMHO to run a Monkey campaign, and their unfortunate absence will require more work on the part of the prospective GM to get their Journey on the road. I would suggest to those that want to give it a go nonetheless, to look up Yaos in the Qin rpg Bestiary for Animal Spirit examples as well as Demons and other celestial creatures, and for the Warring States period map and info in the Qin rulebook (which also has usable examples of Weaknesses and Magic Powers), or the very nice setting map and info (as well as random encounter tables) of the Wandering Heroes of Ogre Gate rpg, while waiting for hopefully new material for the game. You may also look up the "List of Journey to the west characters" on wikipedia for more adventure seeds and background info. Personally, I'll be using the Hoshin Engi anime/manga slightly different premise of a band of immortals joining an heavenly apprentice "monk" on a quest to capture 365 demons in order to free the emperor from the evil influence of a Fox Spirit as my campaign basis.