High Flow Cat? BS or Good Investment

i heard a high flow cat is a good thing to add to your car with a combination of headers, intake, and exhaust. Also heard it will lower low-end torque because of lack of back pressure. What will it really do for me? Will it benefit my car??

[ChrisCantSkate]

well, i recently bange dmy cat out, and i didnt notice a low end loss, of course i dont race my car in the low end, and street driving felt normal. its louder, and with the banged out cat, is makes a bit more exaust smoke at WOT, if i were to do it again, i might do a high flow, but my way was free.