During his time as WBC champion, Vitali Klitschko was described as being the best of his time, and George Foreman stated that he has the best straight left in the division. Both Klitschko brothers are considered the best heavyweight boxers of their era. Having remained undefeated for a large majority of their careers and refusing to fight each other, both brothers remained largely unchallenged throughout their careers. Notably, both brothers were particularly well known for using their large size to nullify other heavyweights. In 2011, Wladimir and Vitali entered the Guinness World Records book as the pair of brothers with most world heavyweight title fight wins (30 at the time; 40 as of 2020).