Vitali got beat by a much smaller poor man's Usyk in Byrd and never sought a rematch, letting 24 year old Wlad take care of it for him. Don't think Vitali has any real chance stylistically.
Sometimes it comes down to style, and sometimes it comes down to character. Usyk would beat both Klits on the same night. Usyk always finds a way to win. The Kilt brothers are guys who put in the effort to an extent, and then retire when things are not going their way.
The amount of cred Usyk receives for beating one top level heavyweight is disproportionate to the achievement. Let's see how he fares against Fury before choosing him to beat the Klitschkos and others who at this stage he really shouldn't be compared to.