So the dealer says my catalytic converter is bad as well as all 4 O2 sensors. '08 with 166000 miles on it. Cost for the converter alone is $1600. I have the sensors and have looked at what is out there for the converter. Any one replace theirs and any thoughts? I see Pace Setter has the y pipe with 4 converters for $400, and Walker has it for $500. Figured I might add a cat back system while I'm at it Thoughts?