Fangio likes 49ers' cornerback corps

--COMPLETE AT CORNERBACK: Defensive coordinator Vic Fangio says Tramaine Brock and Perish Cox are having great camps, and that its nice to have five cornerbacks he can feel confident in.--CB PERISH COX: He says sitting out a year due to the sexual assault charges he was eventually cleared of has made him excited every day to come to practice. Also, despite the success hes having in 49ers as the nickel back working against slot receivers, Cox says cornerback is more comfortable because I dont have to think as much. Lastly, Cox says that he watched a lot of 49ers games during his one year away from football because his former coach, Ed Donatell, is now here. Cox also liked to keep tabs on his former Oklahoma State teammate, Kendall Hunter, too.--QB SCOTT TOLZIEN: Coach Fangio says he was very impressed with how the second-year quarterback performed in the preseason opener. Impressed, but not surprised. Hes got that little extra intelligence you want in a quarterback.--S TRENTON ROBINSON: Coach Fangio says the rookie out of Michigan State has showed slow, steady progress. Fangio says guys who do that often take a big leap in performance at some point.--NO SURPRISES: Coach Fangio says no one surprised him in a positive or in a negative way during the preseason opener. --OGOT ALEX BOONE: At 68", Boone is around 4 to 5 inches taller than most guards. He says he often shocks defensive lineman with his long arms in pass protection. He has studied the style of longtime Chiefs standout Brian Waters closely. Like teammate Ray McDonald, Boone also says hes sought out and received great advice from a guy who knows what makes a guard good or bad: 49ers defensive end Justin Smith.Boone says drive blocking and pass protecting from the guard sport were easy compared to pulling around end. He says the first time he had to pull, he was sweating bullets.Boone says he works very hard to stay coiled on the football field because a guy his size could get in trouble if he failed to get low.Boone says he welcomed the signing of veteran guard Leonard Davis, partly because he welcomes competition and partly because he knew Davis would be just what hes been: a well of knowledge that Boone would frequently drink from!