All good points, but we are talking about an engine whose best exhaust at this time is a hacked up stock manifold with an additional cast iron manifold that has none of the virtues you describe, and you will pay around $400 for the privilege of running it when the supplier deigns to send you one. Your other options are high priced headers that may or may not be available or fit, and have no real flow benefits until you reach revs that stock slants refuse to go to. Gotta remember that the crank goes into terminal harmonic shake at 2250 RPM (4 main bearings). Slants are not high rev screamers so a lot of the popular header design is out the window. The real power killer is the exhaust manifold (I've cut one up) and any improvement over stock is welcome. To find that for a reasonable price is rare.
