We had a 2007 Cedar Creek and currently own a 2011 Cardinal. We were happy with both units, had no major issues with either.
Presently if you look at both Cedar Creek and Cardinal side by side, their features, hardware, cabinetry, and overall quality, I believe the Cardinal is a notch above.
Cardinal has solid wood cabinetry INCLUDING rails and stiles, not sure about Cedar Creek. You can also order upgraded axles and disc brakes with the Cardinal, not available from Cedar Creek. With Cardinal, there is excellent factory support for the Cardinal RV Club, a very strong and committed group of loyal Cardinal owners.
I believe at Forest River, Cardinal is above Cedar Creek.