I was quite interested in go-clair. I suspect it doesn't have large enough airflow since it's so small, but it will be interesting if you can post some data.
Just saying "tested and not recommend" doesn't help.
Since it uses way lesser energy, like 5W for their flagship model on max speed, plus a 35db, the trade off is exactly that. The best way to test it will be to enclose it inside a room for 24 hours and test it against whichever model you have that's HEPA.
Off the top of my head, since its 5W, it's ideal to run it 24x7, and keep the door closed most of the time to keep optimum. Compared to larger airflow HEPA, it has to be switched on high everytime you are in the room, and ideally 8 to 12 hours.
5W x 24 hours = 120W
35W x 8 hours = 280W
Which is why i also do not agree with the "it doesn't work" comments without data.