Investors buying into managed collateralized debt obligations are increasing their scrutiny of the firm handling the transaction, said a panel of asset managers. "The process has become teeth-pullingly lengthy from some investors, but they are doing the right thing," said David Peacock, co-head of structured structured at Cheyne Capital in London. René Herren, head of structured client solutions at Man Investments in Switzerland, agreed, but also noted some investors were lagging in the understanding of the CDO manager's role. The panelists also criticized rating agencies assigning ratings to managers based on quantitative performance data, rather than qualitative and internal practices.