That is correct. Even if you put the stock o2 sensor in your new catless down pipe, you still have no cat, so it trips your CEL light to say that your cat is bad and it's time to replace. They have a fix called a 'MIL' fix but it's only for WRX and Mustangs as I've seen so far. Easiest way to clear the CEL is to dissconnect your battery for about 10 min or so, that way the dealership doesn't charge you like $80 bucks to do it.
I NEED A FIX, i hate resetting my stereo settings everytime i trip a CEL light. I know people have done the B&B Turbo-Back exhaust, what have you done to fix this?!?!?!?!?!?!?!