No drone; they took the time to address the issue. I'm not trying to blow their horn, as I have just(!) sold aforementioned system in favor of a modified OEM SRT8 system. The Corsa system is comparable to the 5.7/6.1 OEM exhaust systems regarding 1st/2nd harmonic attenuation.
I'm thoroughly DISGUSTED at the price they sell for, but it is a seller's market in this case.