ive done alot of reading on both everybody has thier own opion. still trying to fig. out which 2 do or both. ive also read the placement of the vents is important if so please help with a sugg.or pics. thanks guys...oh ya i forgot 04 v700 w/hmf single exh. dalton new blue org. spring 58g wieghts and cover 145fr.148r. jets now ready for air box.. help