Warren Buffett on Saturday launched vigorous defenses of a private equity firm and a mobile home unit that critics say employ controversial business practices antithetical to Buffett's own at Berkshire Hathaway Inc ( In his widely-read annual letter to Berkshire shareholders, Buffett said he would do more deals with 3G Capital, a Brazilian firm with which Berkshire owns a majority of Kraft Heinz Co ( Buffett also devoted more than 1,200 words in his roughly 18,000-word letter to defending Berkshire's Clayton Homes unit, after articles in the Seattle Times accused the nation's largest mobile home builder of predatory lending and exploiting black and Latino borrowers.