Full Race are super nice as well! It's my understanding that these headers were compared & the results went something like Full Race had a bit of a higher midrange while Killer B had a bit of a higher top end but were fairly comparable, but now I'm looking for the thread & can not find it can anybody confirm this? Either way the only reason I'm going with Killer B over Full Race are less welds in Killer B design (especially with the new cast collector). Although I know they both have lifetime warantee to cracks (however I do not know if the warantee is honoured on Full Race if you wrap or coat the header, I do know it is with Killer B).