I remember the issue of the difference between 4 -1, 4-2-1, and equal length header being brought up and answered by imprezer awhile back, and imprezer said that equal length will give the car a unique boxer rumble, a sound that comes close to the WRC rumble. Imprezer also said that it would be mucho dinero for a equal length header. so when i was surfing around, i found this piece http://www.jscspeed.com/wrx/exhaust/gpmoto_header.htm, im just wondering if the quality is good or not and if there are cons to this header.