I came across a full Erion Racing exhaust that looks interesting. But can't seem to find any information on it. The headers look different from most systems I have seen. Instead of a collector box or a 4-2-1 with the front and rear cylinders joined with the one next to it, it is a 4-2-1 with one front and one rear cylinder joined in each pair before finally joining into a single outlet. Each of the two cylinder "sets" has a mounting hole for a O2 sensor. Does anyone have any information on this or insight into the pros/cons of this layout?