D&D - no packing, just a perforated spark-arrestor baffle - header too restrictive, could last forever - if maintained; V&H - packed, short header with sharpest bends looses power, however great mounting system for longevity; Jardine - great header, use stock front lower mounting hardware instead of their supplied hardware - not strong enough (note - the D&D uses the stock lower hardware in its mounting), also packed.
An Ideal system - I nicknamed - "A Poor Man's Force" -
is the Jardine/WhiteBrothers header (same design) combined with the D&D Blast exhaust can - this puppy really rips! Free-est breathing outside of a custom or Force exhaust - which went from 550 to 650 new.
So even if you bought both exhausts new and combined them - you would not be paying the price of an original Force - lol.
EZ