I have a 2002 Buick Regal LS. Acceleration has been very poor on it for the past few weeks and it has been drinking gas and oil like water. I took it to the shop and they said it's because the catalytic converter is clogged. They are charging almost $500 to fix it. I've been told by some people that I can just replace the cat with a pipe and it would be a lot cheaper AND improve power, but have also heard that this is a bad idea and can actually be illegal. Sadly, no one is able to give me good insight. Besides googling it, can you guys offer any advice? Should I save the money and have someone take out the cat or should I shell out the money and do it the way the shop wants to?