Get yourself over to a Hein Gericke shop and try on a HJC AC-11. They have them at £99.99 instead of £200. Infinity are also doing them at that price. Did really well in a recent Ride magazine test.
Can't remember who it was without searching, but someone on here ordered a
Shark S500 Air from racevisors.co.uk for £59.99 delivered. Very smart and that's is a great price - should have been about £110 I think. Also did well in the Ride test.
I've just got a Shark S500 c/o the T.W.O. magazine subscription offer and like it a lot. The visor change mechanism is pure magic.
The bottom line is that a proper and comfortable fit are for more important than a brand name and a paint job.