In spite of the fact that all 50 states don't do emissions, it is a federal law (and stiff fines) if you remove it. There is also a $250 'finders fee' the EPA will pay to anyone that turns you in. This is to encourage shops and your distant friends and relatives to turn you in. That reward is payed by you, ultimately, when you pay your fine for no cat.
You'll find the only few catless cars here are either strict track cars, or a couple very high-flowing cars in Canada, where it is legal in SOME PROVINCES to remove the Cat.
I ran catless on my 95 SLE (supercharged) for a very short period of time when it blew apart inside, until I could get a replacement unit. I lost low-end torque. If you are intent on doing something to the cat, get a high-flow Magnaflow converter. Several of us run those.