I am getting a lot of resistance from the few manufacturers I've contacted so far. Most companies don't want to be in a face off. Despite I told the companies that each product will get its own dedicated review with the results tabulated at the end.
They all fear product comparisons unless they are done in a glossy magazine that dedicates a total of 3-4k words for the entire article with no real measurements or analysis.
Crap in the future, I will just line up reviews and tabulate data in a separate article.