I've used a "normal" light box for some 10 years. It means I can fall asleep at bed time during the winter instead of several hours later. I've tried the P1 instead of the lightbox for two months now, and I have to say that this little blue-light gizmo is just as effective for me as the lightbox.
It's also portable, which means if I go away for a week in winter I can still sleep normally. I find a setting of 75% for 20 minutes each morning at 2-3 metres from my eyes is best (I put it on the floor about a metre from my feet - don't stare at it, just keep it visible).
The only negative I found is that the LCD display is really faint, and I can't find a "contrast control", but it's readable, and there's nothing much to read anyway. I suspect the price will come down over time, as it's a new type of product and the components are not at all expensive.
Nonetheless, it's competitive with the "big" light boxes, and does seem to do the job well. They also do an "M2" model that has built-in rechargable batteries. I think this would be better as portability is one of it's benefits.