Just to add to my review
I take the visor off after each ride / weekend to wipe mud off helmet / visor
The second time I did this the right hand screw would start but only go in a few threads. Seemed the brass (?) insert in the helmet was partly stripped / cross threaded.
How a metal insert could have been stripped by a misaligned plastic screw beats me!
Anyway, I packed it out with some plastic washers and tightned as far as I could. Wasn't pretty but worked ok.
Last ride of the season I took a tumble doing a gnarly climb on some rocky terrain. Banged my head 2 - 3 times rolling downhill. No impact passed on but decided it was best to "retire" the helmet.
Have ordered another MX 470. Only downer was the discount price i got the first one for was no longer available - cost another $80 !
Still not my favourite helmet but at $250 cheaper than the next well vented alternative (Leat 5.5) it was an easy choice