so, i've gotten a good amount of riding time with this Shark Speed-R, time to give my review.
what made it stand out for me was the "sun visor", which is on-the-go tint; easily flipped either up or down for convenient tinting. the plus side of it was Shark's designing and aerodynamic testing to make this helmet "for the naked bike riders", like Streetfighters, cruisers, etc.
when I first started riding back in 08', i used a used HJC helmet. it was huge, uncomfortable, stinky, and looked hideous! i upgraded to a Shoei RF-1000 when i saved up enough money, and i loved that helmet all the way up until i bought this Speed-R.
the Speed-R fits nice, cushioning and inner liners are made of nice materials that are easy to take out and wash when needed, and there are proper pressure points to keep the helmet in place, but wont give you a headache. the Shoei is just a TAD bit more compact around the lower shell of the helmet, which helps with looking over your shoulder, so this gives a sense of the helmet being smaller and lighter, but in fact the Speed-R weighs 130 grams lighter.
aerodynamics of the helmets, the Speed-R wins out no doubt. the Shoei has simple features, where as the Speed-R has a rear lower wind de-buffeting spoiler lip and two upper spoilers to help with high-speed stability and also creates a venturi affect to cool the inner liner. the wind de-buffeting spoiler almost eliminates that "back and forward" rush that throws your head around when riding on the highway and above the windscreen of your motorcycle (if your motorcycle has a windscreen).
to me, the Shoei costing $550, didn't give me the sense that it was a "top of the line" helmet. the Speed-R shipped for $465 from Europe, feels like a top of the line helmet; with it's inner liner material to the dual visor, to the outer shell, paint, and branding, and finally to all the aerodynamic tweaks and features.
+1 for Shark.