I'm actually surprised some frequent flyer types would poo-poo such an opportunity.
Was on the trial, and a valuable expeirence. There are no doubt a lot of things that people who spend 1-3yrs working on a project won't find, that those who travel through airports frequently will.
I ended up filing around two (handwritten) pages of feedback, identifying various weak points or issues with the terminal, signage and other matters that need to be addressed. The more people with a clue who participate in these trials, the more chance they have to get things right - and hopefully not make the same mistakes in future.