So, let me discuss the two (very slight) negatives first: 1. No helmet manufacturer has an accurate size chart in my experience. Almost always, they recommend a large for me, and almost always I have to buy an XL for it to fit well, but have sufficient room inside to keep my lips from polishing the front of the helmet. The size guide recommended a large in this helmet, and I normally would have ordered an XL; however, after reading the reviews, I ordered an XXL and it fit me perfect. 2. There is a noticeable whistle from air coming in between the shield and the shell at the forehead. Possibly due to increased air pressure, this goes away at speeds over 30mph. It can get a bit annoying when putting around town, but that slight annoyance is out weighed (quite literally) by all the other benefits to this helmet.
The goods are too many to list and discuss with any degree of accuracy this helmet deserves. It is light as a feather, solidly built, well ventilated, and the Transitions shield is amazing. It never gets exceedingly cold here in Santa Barbara, but my morning commute has been averaging 40-50 degrees Fahrenheit; I haven't had any fogging problems with the shield. Ironically, the few days I've worn my prescription glasses, they were fogging up on me and the shield remained crystal clear even at a full stop. I've now logged almost 600 miles in this helmet and haven't given my old Arai's, Shoei's and Nolan's a second glance. After adding a Bluetooth com system to this helmet, it'll be my primary for quite some time to come.
Did I mention it is a race-ready helmet, it is full carbon fiber construction, it is under $1000 (if you want to see what quality you get from other manufactures for less than that price check out the crap HJC tries to pawn off on you) and it looks sexy as hell. Akuma seems to be trying to change what people expect to get for $300-$400 in a helmet, and I think they're doing a fine job. This is easily of the same quality as my $800 Arai. If you spend more on anything else, you're making a HUGE mistake. Get one.