I have no experience with Kai brand, but it looks like they're on par with Karen Kay Buckley.
My go-to scissors are the 7" dressmakers shears (Gingher) and the KKB applique scissors (around 4"--small, for tight corners, trimming "dog ears," slicing through small HSTs and such). I might use longer dressmakers, but I have small hands and the larger scissors aren't as comfortable.