RazorI can see why...the Hayabusa tries its hand at speed, and the name translates to peregrine falcon which is known for its vertical hunting dive speed of 290 to 325 Km/h (they say this is the fastest of any bird at diving). From this, I can probably assume that the vertical glide is the faster one, and that the difference in glide is probably intentional (quite likely for a company that has such an attention to detail)