Have you actually done this mod yourself, or are you just talking based on no actual experience? I bought a used Fiesta that had the muffler delete and the
drone was unbearable. It literally hurt my ears after awhile. I added the Vibrant before the tailpipe and it did WONDERS for reducing the booming resonant
drone that was present before. It was a night and day difference and I think anyone would be
hard pressed NOT to notice a substantial improvement. Add to that the fact that MANY of the reviews on the Vibrant specifically mention an improvement in the droning of the car. Is it completely eliminated? No, it is not. Is it vastly better and infinitely more tolerable? Yes, most definitely. Obviously, a thermal or a Milltek is a better solution, but for $70 I now have a car I can live with and the exhaust note sounds really nice without being obnoxious. I can't speak for all the technical reasons why the resonator can or can not reduce
drone. All I can do is share my experience so that others may profit. I read about 2 dozen threads on the subject and got really conflicting opinions, so I just wanted to share my ACTUAL real world experience. I am very satisfied with the muffler delete with the addition of the Vibrant until I decide to upgrade the entire exhaust, and it most definitely improved the booming
drone that was present previously. I would also recommend doing the
symposer delete as that also really helped as well.