Here's my feedback on this. I had rasp from hell when I put on Stainless Works catless downpipes with the Corsa cat back. These cars are notorious for rasp due to how long the exhaust pipes are.
https://www.youtube.com/watch?v=128SB_RY0UQThe factory exhaust has 2 cats, 1 x pipe, and 1 H style rear muffler/cat before the rear mufflers. If you go through the trouble of just replacing the mufflers, you're gonna be pretty disappointed. Anything after the cats + x pipe, + rear cat won't change the tone too much. I do, however, enjoy the muffler delete sound, but I feel at high way it can be a little noisy.
https://www.youtube.com/watch?v=w8v5Sw_lTX8If you decide to do what i did with the catless downpipes and corsa cat back, I strongly recommend getting a magnaflo (or alike fiberglass resin) muffler to cut down on the rasp. I know one of the ecoboosters had a lot of luck with my stainless works catless downpipes and MRT axle back.