You guys are looking at what I've stated here with the 2 shops and thier comparisons so I restate the jist.
performed a before/after test with OTS (Off The Shelf) Cobb maps to see what would happen, since this if fairly common as not everyone gets tuned. When that was done they tuned the car and that plot is shown as well, it's the one that says Stage II tune vs. Epic Motorsport Custom Tune.
tested the header (FULL REVIEW HERE)
on a tuned car then swapped only the header and retuned. They included all kinds of graphs and data logs.
IMO the data from both is relevant because it shows what happens if I have a COBB OTS stage II car and I put on the Killer B Header, as well as what you can expect if you have an already tuned car and and what to add our header.
I'm working on collecting some more data, but it takes time. Unlike most manufacturers we're offering our data, collected by other shops, in a public forum. Good or bad it lets the consumer make a more informed decision. It's a better than the typical "expect midrange power increase" with our header. Right?
Phatron, check out EFI's review/data, and by all means call the sources of these tests. Chris at EFI Logics and/or Robbie at Epic Motorsports can answer any questions you have. I'm a mechanical engineer not
a tuner, so they can much better answer your questions and they have no vested interest in selling headers.