IPD vs EST vs Borla - Volvo R Exhaust Comparison Video
all cars have an OBX catless downpipe and were revved by the same person.
ATR-6550 shot-gun mic hooked up to a Zoom H1 audio recorder, placed about 13 feet behind each car
this video only shows you what they sound like from outside, I will have to take each car on a cruise and see if I can also capture what the noise (and/or drone if any) is like in the cabin for a more full review. I own the Borla setup and it does have some drone but its not intrusive at all or irritation just enough to let you know you have an exhaust that will go crazy at WOT
some other related videos:
ELEVATE / IPD / BORLA / STOCK exhaust comparison
EST Exhaust link:
IPD Exhaust link: