www.boxertrix.com

Can't comment on the models you posted but any Shoei medium size fits me like a glove. The Neotec is a favourite, tics all the boxes. The Hornet is very good, no buffeting, good ventilation and the visor is very big so you get a good view. I bought my Neotec a over a year ago at the NEC for cheaper than what they are advertised for now. A search on Google shows you can bag one for as little as £350 . Normal prices is close to £400. Have a read here: http://www.webbikeworld.com/ if the helmets that you listed has been reviewed.

I had a quick look on the Sharp Helmet test site. I think their ratings are at least a useful starting point.

Looking at your budget and just a bit above, the top 3 rated system helmets were all Caberg. Might be worth trying a couple on.

The top 3, were Trip, Konda and Duke.