Opinion needed

Hey guys, about a month ago I installed a CA smog legal X pipe from magnaflow (4 cats) and bolted it up to an American Thunder Flowmaster exhaust system. Quite honestly I was disappointed in the sound but on the other hand I do like the back pressure and performance I gained from it. Well one of my catalysts has failed, I probably have 1000 miles on the system and now im getting this rattling sound at idle that is driving me crazy. Long story short the dealer I bought from is attributing my failing cats to my car, which maybe true and quite honestly i could care less. He claims as an example, if my car is running rich, any unburnt fuel that gets into my cats would destroy them and negate a warranty or defect issue. His claims is that cats dont fail, how an engine runs determine the fate of a Cat. After going round and round with this guy I figured I'll cut my losses. I spoke with magnaflow and they do warranty the item but I need to go through my dealer for the claim.

My thoughts: Purchase an offroad BBK X pipe (bbk shorty headers installed) and run this with my exhaust. Then for emissions just bolt up the Magnaflow X pipe. Seems like an easy decision to make but I just need some encouragement to pull the trigger i guess. I'll get the sound Im looking for, however on the other hand I dont really want attention from law enforcement. Thanks for letting me vent, by the way you guys post some great material on here, keep em coming.

Thanks for the reply, the dealer is discountconverters.com, I stopped by the exhaust shop that did the install for me and he said what you both posted. He felt if my car is running that bad it should have screwed up the upper cats just after the headers not the one that is going bad. Im not usually a pushover, but with my zero knowledge of how cats work and this guy just aggravating me with no sign of him budging I just let it go. But again the advise is appreciated, will see if I can deal directly with Magnaflow in the morning.

Grover - both of your cars look awesome, nice work. Were you at the Fabulous Fords Forever Show at Knots Berry Park? Some of the nicest Foxbody's I've seen so far, (owned mine for just over a year now). Also Im trying hard to build a bitchen car and keeping CA smog legal. Are your cars set up pretty wild? I'd rather not have to duck and hide around Law enforcement and be able to smog it every couple years without spending a week in the garage to get it ready to pass. Thanks.