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went to a 100 cell high flow cat and it felt alot more torquey and responsive (plus it sounded 10 times better)
All those brands will be good,just make sure you get a 100/200cpsi highflow metal-core cat or bash the factory one(shhh).
Just about every day I smell 1 or 2 cars with this done, its like pooooooohwww wtf d!ckhead *windows up, vents closed*