Instead of Settelment... close accounts?

Instead of settling with the cc's, why not just close the account and set up payment arrangements? No interest is accrued and the interest rate is good? Citi just offered to close my account and put me on a plan to pay off the balance within 1 year. Low interest rate. I can manage that. How bad will it damage my credit to close all of my cc's (6 in all)?