I trust that Fiat will have given extensive thought to noise levels, having already used a raucous exhaust on the 500 Abarth and Abarth Cabrio (notable since it also has a retractable top). The sound was never unpleasant in my Abarth, and would quiet down surprisingly well – nearly undetectably so – at cruising speeds. It was uncanny how it could sing a full range, and the sound was never boomy or disagreeable. In fact, I don't think I turned on the radio in my Abarth for all three years that I owned the car, because the exhaust made such a sweet sound that I didn't want music to interfere with it. Someone posted on a Miata forum a link to a Car & Driver noise comparison between the ND Miata and the 124 Abarth, and the 124 was equal to or better, i.e., less noisy (sometimes significantly less) than the Miata. I don't have the details, such as whether the test was top up or talk down, or specific numbers at hand, but there were numerous measurements at various speeds. Every road test has indicated that the Fiat benefits from thicker rear window glass and roof/cabin insulation. I had been concerned about the exhaust sound, but I'm now convinced that it will be exactly right.