pre cat

Hello people not sure if it’s been asked before but can’t seem to find it anywhere. is the much of a difference between buying a turbo back down pipe and just smashing out the pre-cat material? 2010 seat Leon fr 2.0L petrol

Hi all I am planning to get my 2019 2.0tsi dsg estate remapped. I am looking at a stage 1 which gets me around 245hp Reading on here there seems to be a lot of talk of removing the precat. Now, showing my ignorance, is the precat in the downpipe? and is it a case of just removing the precat...