glad i live in oz, the as1698 standard is ridiculous to pass compared to some countries. which is probly y our helmet range is so limited because they have to make them different to pass our standard. i work in a motorcycle accessories shop and the best advice anyone can give you is buy the best fitting helmet you can afford. if a $1200 x11 or corsair doesnt fit properly dont buy it, youd b better off with the $100 helmet that fits like a glove.
That being said youget what you pay for in helmets. this is not limited to shell construction, but the liners (removable or not) ventilation and graphics. it is amazing how much some of these companies get paid to design graphics for lids.
buying a helmet is an investment. more expensive helmets tend to last longer, as the padding tends not to wear as fast. the more you ride, and the harder you ride the better the helmet you should be lookin at. cracks me up every time i see a guy on a litre bike with shorts, singlet and lid worth $80.
i really like my SHARK RSR2, and i have a few SUOMYS and they hardly get worn any more. i love that the back edge of the SHARK allows for a comfortable full tuck without digging into the back of your neck. the new FULMER helmet is this way also for alot less $