@Andrew Shadow and
@jonjonboo are exactly right. You need to stick your head in a few different helmets. Nothing anyone tells you of the, 'brand xyz is best' is very meaningful if the hat doesn't fit. I tend to go look at the hats for features - kind of closure, style of locks (I want a modular - it is easier to talk to someone at a gas pump with the modular wide open), ventilation, weight, $$$$$$$$$$! first, then find a salesman and talk to him about what he has. Then start trying them on.
The only thing I will add, is the padding - cheek, jaw will break in, so if it feels a bit tight there, no worries. However, the fit around your forehead is due to the shape and size of the rigid foam inside the shell. That won't change. Someone here sanded the foam inside his Shoei NeoTek 2 early this year and made a good fit for his head. I'm not sure I would have the guts to do that to a 500$ hat.
Things to consider if you go modular: type of buckle/release under your chin; type of locks that hold the face part down; is there a sun blocking visor that retracts?; can you raise the front w/ the sun visor down; does sun visor go all the way up into the hat?; visibilty, i.e. size of opening you look out; ventilation* or lack thereof, noise level (this is a hard one), does it have integrated comms?
Good luck. You might check Fort9 and listen to what he has to say about helmets. If nothing else he will suggest some things to consider even if the info is obsolete.
*My Shuberth (now pushing 5 yrs old) has very very poor ventilation. A salesman at a mc rally said the new model had 40% more airflow. My response was 1.4 times zero is still zero. (Yes I had the ports unblocked).