Well first off its not "they" or a company trying to market anything.
It's one guy who spend his own money trying to perfect a suit. But he's not just some ordinary garage shop joe tinkering around, he used a lot of expertise in materials and body shape dynamics, r@d and the help of several experienced engineers including that crazy french pilot/engineer Ives Rossy ( his neighbor).
He has his data backed up with more r@ d than you could imagine and invited other manufacturers to test his claims in a comparison study.
Since he's using his own money he even told the current manufacturers they he would pay to comparison test his suit against theirs.
Unfortunately none of them really stepped up to the plate, though they did show interest.
The project has been totally dropped due to the designer having 2 kids and moving on, so these wingsuits will never see the light of day. Its to bad the 8 years of significant R&D will be thrown into the back room never to be used.