Not the Question wrote:
Those aren't competitor's versions of the 4%...
Berg is referring to the Hoka Carbon X, Skechers GoRun Razor Elite, the Saucony Prototype Ward wore at Boston, and the new Adidas Prototype that has been floating around.
To answer the original question, those models weren't tested by the study.
Also the Brooks shoes the Desi and Ritz have been wearing.