I picked up one of these on chainlove. It arrived, I tried it on- the one size thing works very well. I'm usually between a medium and a large and this was really nice. I already have 2 other helmets- a catlike whisper (not the plus) and a giro aeon.
As much as I liked this helmet, it felt much heaver than the other 2. Then I put it on my scale. Forget the claimed weight of 280g- more like 350g.
The whisper weighs about 280g and the aeon is just ridiculously light (around 210g), so I packed it up and it's going back. Another drawback is the "kask" emblems that block the vents you'd otherwise be able to put your sunglasses through and have them stay .
Just not worth the extra quarter pound!