Power-up itself was dope ^^ and was looking pretty beastly within the first two chapters of it's introduction but fight dragged on way too long imo so it a lost it's impact really quickly particular since it's a cartoonish type PU. PU itself took the seriousness out of the fight from inception coz of the nature of it but it was entertaining initially so was aight, but then Oda decided to drag it and then it started getting pretty boring especially with all the rubbish cliff-hangers that didn't lead to anything. Moreover, for some odd reason I honestly can't comprehend, Oda decided to have Kaido mock Luffy's ability and then have him put Haki on a pedestal, which only killed the already dying impact of the PU even more. Then to make matters worse, Oda then decides to end the fight in the most uncreative way you could ever imagine lol. I mean for a PU that is said to be only limited by the User's imagination, having that be the finisher was pretty ass but I'm over it lol and glad it's over.
5/10 for me coz of the first two chapters.