The HMF-SL300 has tilting motors to move the quadcopter forward and backward instead of tilting the entire quadcopter. This allows for the FPV camera to point nearly straight forward and still be able to see clearly at high speeds. The downside to this type of frame is the extra weight of the bearings and servos required to tilt the motors. However, they can be compensated for, somewhat, by using 6" props. I haven't seen many of these being flown, but that is probably due to the higher complexity of the build than required by flat frames... kind of the same reason there aren't many tricopter pilots.
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You can get your own here:
HMF-SL300 Frame: