I was there yesterday to run through their tests. An interesting day for sure, and I'm really looking forward to getting the results sent through.
Didn't take note of many numbers as we went through, but like Assassin it was my legs that gave up (or, rather, a couple of muscles that aren't normally that exercised when riding upright) and not my breathing, although that was getting quite rapid towards the end.
Main comment was that my breathing stayed remarkably slow and deep through most of the CPET, which also helped to explain what I think they said was the highest air volume figure they'd seen through their study, peaking at 174 litres/minute.
I think they are finishing the study tomorrow.