I'll play devil's advocate here...
I'm looking at the optimized Y-pipe I bought from Warmonger (thanks Tom!)...and I'm not really seeing any huge difference between what's on my desk and what I'm looking at in those pics (on the front 1/2). In fact..I am not to crazy at all about the part after where the two primary tubes come together...the Y looks nice...but the real critical part is where it goes into the single outlet...it looks kinda squarish to me (right before the flex pipe)...and should taper as much as possible.
