Gimmick, they can't convince people to change their sparks plugs at regular intervals so they invent gimmicky plugs that they can convince people will gain 100 hp.
Its not the plugs that give it the extra 100 hp....... its the stickes..... everyone knows that stickers give you power
'02 GMC RCStepSide 4.8 , Thumpr Cam , 3200 Stall , OBX LTs , MSD Wires , TrueTrac , 4.10s , 3/5 Drop , bolt in traction bars by LSX Powersports , EFI Live tune by LSX Powersports
15.2 @ 90 , 2.3 60' (Only mods at this time , LTs)