It's really sort of pointless without a turbo unless your stock cat is clogged because the OEM cat can already out-flow almost any Honda motors. High flow cat's are hard to light off, so they don't work as good as the factory cat, and probably won't help you avoid CEL's on a OBD-II car.

I don't have a cat on my car right now, and it sucks getting gassed out at drive-thru's and stop lights. Really takes its toll on you if you're hungry & stomach growling kind of thing like I was today. Makes me want to vomit sometimes. Carbon Monoxide kills people in high doses, so it's not a good idea on your daily driver.