Greg is right. There are two O2 sensors on the 93-95 cars, one each for the left & right cylinder banks. They are located in the down-pipes for each bank. Removing the cat should not affect the O2 sensors.
And while it's true that the cat produces CO2 (carbon dioxide) as one product of the catalytic reaction, the benefit of the reduction of carbon monoxide, oxides of nitrogen and unburnt hydrocarbons (NOx to nitrogen gas and CO and hydrocarbons to water and CO2) far outweighs the risk of the added "greenhouse" gas CO2.
A healthy catalytic converter does not pose a significant flow restriction to the exhaust gas. "Healthy" meaning that it's not clogged with deposits from running too rich or oil burning and that it hasn't been damaged by overheating etc. I've not heard of any compelling testing that's shown removal of a healthy cat will produce noticeable power gains. Not on this car (small displacement, low specific output) anyway.
More and more jurisdictions are instituting emissions and inspection programs. Yours may not, but you might want to check if it's in the pipeline before removing the cat.
And as Greg said, the noise will go up significantly. It will sound much less "refined" and much more raspy. It may not be something you'll want to live with. If you do remove the cat, make sure you can re-install it if you don't like the sound.
