I've always had a Dodge and a Jeep and have always used Flowmaster mufflers. I've had most of the different series they make and really liked the sound. But now I have a Hemi 5.7 in the Jeep and I've tried a 50 Series Flowmaster and it sounded great at idle but had a rattling noise at 1200-1500 rpm. The bad news is that the Hemi takes about 30 seconds on a cold start remains in this speed range. It's loud, obnoxious and sounds like crap. I tried putting a resonator, it helped, but the rattle remained. So I finally took all the advice and bought this Magnaflow muffler, it's the first I've ever had and I will be buying many more. It's stainless steel versus the steel Flowmaster, the welds look better and the sound is very different. At no rpm does it rattle at all. From idle through 700 rpm to 4000 rpm there is no bad sound. It just sounds amazing all the time. The sound is deeper and softer but just as loud as the Flowmaster, I agree. It's hard to find words to describe the difference, but I can honestly say it's a day/night difference and everyone at work noticed it right away. I recommend this muffler for Hemi Trucks/Jeeps.