I got the borla pro xs, when I got it originally the main goal was to be able to hear it when I turned the truck on, or when I got on it. Sadly it is still a little too loud for me. Sounds nice and loud on cold starts, while cruising below 2.2k rpms sounds stock. Above that oh boy it gets too loud in the cabin.and if you gas it, it will scream. I love the low rumble and crackles but its just a little tad too loud for me. Although I would say its way quieter than the flowmasters 40+ series I've heard on similar trucks. Gosh are those flowmasters loud. If I had to do it again I would probably get something just a little quieter and call it good.