Vitali does not have his brothers speed, accuracy, or power. He was throwing arm shots against Kevin Johnson. Vitali has so many flaws right now it's ridiculous. But because the division is so weak and many of the contenders don't have championship level skills, he can get away fighting sloppy. Chambers is probably the most skilled heavyweight behind the Klitschko brothers, and he's actually training hard. Chambers would pick Vitali apart.
I would agree that Vitali would be easier to beat than Wlad. Since Wlad is better at beating pure boxers, and Vitali the other way around against heavy handed brawlers. But it still won't be a easy for challenge for Chambers, since Vitali is no duck walk, and he beat Gomez, another extremely skillful boxer...