No not yet, I'm not convinced that the shorty style header gains you that much over the stock manifold, and I'm not sure i want long tube headers. If i ever need to buy new manifold then I might get some shorties to replace them, most bolt right in place of the stock manifold so i wouldn't need to modify the downpipes.
I plan on a complete new performance manifold back. 2 1/4 into 2 1/2 into a flowmaster Y pipe, 3" into a CC, and then a 3" in/out magnaflow RV type muffler.