OK I needs some input from the group here.

Last year I had to replace the rear cats on the SRT6 (120,000 miles) and after researching and digging up my best deal on the entire exhaust section from front to rear cats from Mercedes at 2500 for both sides, I chose to weld in some high flow cats for less than 400.00.

Some 15,000 miles later, I have a rear O2 go out on the left side and it is showing signs of ceramic material hitting the old sensor...a few weeks later and I am starting to hear the front left cat start to rattle. That means I have a few weeks before I throw a CEL and have to replace.

Has anyone here replaced the front cats and if so what was used and were there any issues?