Arai RX7 GP for me, fits very well once I custom ordered some different thickness pads, a beautiful helmet.
The downsides are A - Weight, compared to top line Shoei helmets the Arai is noticeably heavier and B - Aerodynamics, again Shoei for ultra high speed riding ( 120MPH plus ) much less 'wobble' and I can look behind at these speeds with the Shoei and it is firm and unmoveable, the Arai does shift around a little, even though I have had it fitted properly and spent the money on the 'bespoke' pads.
I also have a Colin Edwards Yellow '5' RX7 RR4 - which was signed by Colin at Le Mans two years ago, took me ages to get rid of the autograph once I had decided it was to 'posey' lol. However this DOES fit me better than the RX7 GP, I think the shell re design suits certain heads, perhaps not mine.
Have I gone on too long....