I thought it was really good! It’s got some great QoL improvements that I wish they had backported to the base game, honestly. Also, it addresses some flaws in the end of the base game, making it a clearer what was supposed to have happened (while still leaving some stuff open, it is a Xeno game after all).
Also, I won’t spoil anything but if you’re a long-time fan of the series there’s a lot to like.