lol, if you want to know just how much a turbo quiets your car down, before I went turbo, I had the stock cat and an aftermarket muffler on it. Sounded nice and deep, but it was a bit loud on the freeway, loud enough that it was hard to carry on a conversation. Threw the turboon, and itw as the same at idle, but anything higher than that, and the exhaust was almost silent.
Before I started ripping my engine out for the rebuild, I made up a new exhaust that uses only some bent piping, and 2 glass packs. That was WAY more quiet than the old setup. I'll have pictures of verything when the engine is back in.
If you really want something decent, go buy whatever muffler you want, keep the stock cat in there, and take it to a muffler shop and have them put in whatever size piping you want, all mandrel bent, and make sure you have a resonator in there, or it will be buzzy. Total cost should be well under 300. Looking more at about 250 or so for something better than an aftermarket system premade for the car.