The Arai RX-Q Motorcycle Helmet is the evolutionary next step in Arai Helmet design, designed to be the Ultimate Street Helmet. The Arai RXQ could also be considered the "Corsair for the Street" as it includes many of the innovative features of the Arai Corsair V Helmet, albeit at a lower price point. Or, if you've really got to have that full Corsair shell, but want shape and venting in the RX-Q style, check out the Arai RX-Q Pro Helmet, launched at EICMA 2015.
The Arai RX-Q Helmet has an intermediate oval shape and fits similarly to the Arai Quantum 2 Helmet. The changes in cheek pad structure should allow it to fit a variety of head shapes well.