They both alternate has the supposed best brother. Prior to the Puritty lost, Wlad was viewed as the better.of the two. Afterward, Vitaly took the spotlight, but he pretty much was viewed as a hype job after the Byrd fiasco, and Wlad retook the lead, only to lose it with his two disastrous performances against Sanders and Brewster (and even Peter to a lesser degree). Afterward, id say Vitaly was pretty much viewed as the better of the Klit (rightly or wrongly), until his retirement.
All in all, while i like Vitaly a lot more than Wlad, im not so sure he was actually better. Sure, he didn't had the vulnerabilities of Wlad, but he was much less skilled, fast and agile. He's a bit of a question mark. He lost against the two best fighters he faced due to injury/cut, but the rest of his resume is very underwhelming. To his credit, he was mostly dominant against them, but as i said, it's hard to rate how good he was (or wasn't)