I think Chageav was heavier handed coming in near 250. And I think Browne sacrificed his durability and strength getting down to that shape. I don't think Lucas would have been dropped or bullied if he fought at his natural weight.
His chin is a 7, he was also rocked against Rudunko and Bahoeli (can't spell either) his recovery is excellent though. He's similiar to Tyson Fury, fantastic recovery and heart, will rather die than lose.
Bad question. Guys can get knocked down, and get back up. Other guys get knocked down and are totally discombobulated. While still others take big shots and keep on ticking. I don't think browns chin is horrible, I think his punch resistance is. Ruslan isn't a huge puncher. He wobbled Browne with a punch that barely grazed the top of his head at one point. I'd rate Browne's punch resistance as a 5.