Lets talk about features. That's right, this helmet is essentially a Hammerhead with a removable face guard. The face guard is held on with three screws on each side of the helmet. The hardware and mask adds some weight. The Hammerhead weighs in at 305g while the Switchblade weighs 665g.
Ventilation is good as well.
Though it is hotter than a normal helmet while climbing, the vents in the face guard provide good ventilation at higher speeds. The ventilation in the rest of the helmet is top notch. In fact, this was the first helmet that I could feel the air being pulled out the vents in the rear. Fit was good, though I feel that Giro helmets in general tend to favor a more round head shape. This fit me fine fore and aft, but had a little too much room on the sides.