Hi. I have heard the Thunderheader pipes several times. In fact, I was going to go with them UNTIL I got turned-on to the Hard Krome product. The Hard Krome pipes sound MUCH better (deeper, lower, throaty sounding). It keeps the Harley sound intact. The Thunderheaders have a good sound but loose against the Hard Krome on looks (no heat shields), dyno testing, sound, and warranty for blu-ing. I have a couple of friends who have Thunderheaders. They both said they want to upgrade to the Hard Kromes after hearing mine.
Hope this helps!
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