I know you (actually the guy at MSDS) said
MAX, but I have trouble believing 40-50 hp gains.
Not that I think they are a bad product, but everyone needs to make sure they take vendor hp quotes with a grain of salt. A more appropriate hp quote would be "average" or "expected", but hardly anyone says that because they don't sound as cool.
Like I said, I don't think the headers are a bad product, and I'd like to put a set on my car someday. Just not now. $$$