is saber build on kai sa really that good ?

It's a lot of fun. I'm not even an ADC main tbh but I just fel in love with Kai'sa's gameplay. Saber's build is just way too much fun for me but is it actually good enough to have an impact on the game ? I can't find a single Kai'sa player using it like Violet. Is it situational ? Everyone seems to prefer the classic build.