When I went looking for exhaust options for my 2019 Silverado Custom Trail Boss I found plenty of catback exhaust options available, ranging from around $600 to well over $1200, and of course the straight pipe option for around $110. I didn't want a loud exhaust, just something to make it sound better and get rid of the flapper that was killing power.
After some searching and some dyno feedback from Engine Masters I ended up purchasing a 3" offset stainless Cherry Bomb Salute Muffler and 2 stainless clamps for a total of $80 from Summit Racing.
The removal was straight forward, cut the existing muffler out while leaving as much of the factory pipe as possible. The downfall of the stock exhaust is the 2.75" diameter pipe that needs to be stretched to 3" to slip fit the muffler. I bought the Astro Tools pipe stretcher to stretch the pipes and it worked flawlessly, another tool I should have bought years ago. You could take it to a muffler shop to have them do the same thing if you didn't want to buy the tool.
Install is simple, slide the clamps on loose, fit the muffler to the factory pipes, and tighten the clamps. You can save yourself a little money by welding the muffler if you have the capability to weld stainless, again a muffler shop can do this for you.
Overall, sounds near stock at idle and moderate throttle application. At WOT it is noticeable but not wake the neighbors loud. There is no drone but it did increase the cabin noise at highway speeds. The best part is I noticed a huge improvement in throttle response, especially in city driving, and my fuel mileage increased by a solid 1-2mpg. My only regret is not doing this when I bought the truck.