Other VTOL + Forward Flight projects have been successful, but have usually required external vertical thrusters in the form of multicopter framing and motivation. This method requires a lot of battery power that the craft must carry with it for the entire flight. An external framing system for the multicopter motivation leads to unnecessary and in some cases, extreme drag, reducing forward flight efficiency by 25% or more.
The Bird of Prey II incorporates the vertical thrusting gear into the wing airframe in an aerodynamically sound way that can also be used for thrust vectoring using the louvred flap covers. It also makes use of battery alternatives to achieve maximum flight time.
Some other VTOL projects use a 'plank' style glider as the base. This works well, but results in a really crazy wingspan. The blended wing design gives maximum lift and minimum wingspan for easier ground transport.