In the process of trying to buy a helmet and I feel that I'm stuck between two sizes.
The medium passes OMPs "should not move by more than 20°" test, but it doesn't feel right. It feels like the internal padding is pressing a little bit on my head. I.e. it's not just in contact with my head, but is actually pressing into it slightly. There's not a huge amount of pressure but it's there. It's a consistent pressure however around my entire head, and it doesn't feel uncomfortable per se, but on the other hand it's also not comfortable.
The large feels comfortable, my head is in contact with the padding, but there is no pressure, but it fails the 20° test miserably.
I've uploaded two videos here that might help.
I'm currently sat here with the medium on and plan to keep it on for the next hour or so just to see if I get used to it, but I have to say it doesn't feel "right". Albeit, with no experience who am I to say what right is.