It's funny you mention the KZ lineup... The K3 Pro is definitely miles better than the ZS3 and ZST that I have, for different reasons, but for some reason I find myself reaching for my ZS5 quite a lot. There is something that's just really fun with those. It's technically a step or two behind the K3 Pros, but it has for me quite an engaging sound. The K3 Pro, however, is much more refined without presenting itself as clinical. I've listened to the Exclusive 5 a bit more, and while I am very much enjoying it, for some reason I feel like there's just something missing, some excitement that's been misplaced somewhere. I'll keep chiming in as more burn in hours pass and I can better compare the various IEMs I possess. My Chi-fi contenders include the K3 Pro, Ex. 5, KZ ZS5, ZST, ZS3, and I'll throw in an outlier with the Beyerdynamic Byron wired. Should the YINJW P8 arrive on the slow boat from China anytime soon, I'll throw those into the comparison as well.
Give me a week or two and I'll try to write something up.