I bought one of these a while back:
http://www.argos.co.uk/static/Product/partNumber/3334807.htm?CMPID=GS001&_%24ja%3Dkw%3A{keyword}%7Ccgn%3Apla%7C%7C3334807%7Ctsid%3A11677%7Ccn%3Apla%7C%7C3334807%7Cmt%3A{MatchType}%7Ccrid%3A14542145259
I’ve added low profile thumb turn screws for easy removal.
I have to say for the money I’m impressed and think it is a viable alternative to a Giro Switchblade type helmet for a fraction of the price.
I’ve gone through 3 Switchblades by landing on my head and cracking them years ago and wanted something I can ride to my jump trails with, then add the chinguard for prevention of expensive dental bills.
It fits my head at 58cm and for the price might be worth getting a couple….don’t be put off by the Argos label, you can cover with stickers! 🙂