Considering the fabrication cost ($2,000 is a low estimate), the BTU loss to underhood air (5-10 X the exposed surface area), the 3-5 year life expectancy due to corrosion and vibration fracture (compared to 20 years for cast iron) IMHO it's only valuable for competition. My engine bay temp with coated manifold and shrouded turbo is still too high.
I've read comments that individual pulses have a stronger effect than the single output of an iron manifold, but that they should be significantly different lengths to avoid arriving at the same time.
