The term "speed bows" doesn't really apply in the sense that it once did. Speed bows generally referred to units with very short brace height, radically reflexed risers and extremely stiff drawing cams. They also tended to be louder with more recoil and vibration.

Nowadays with parallel limb style bows companies are capable of creating more manageable speed bows. The parallel limb design tends to creat a relatively large brace height and also channels away most bow jump thus making many speed bows today a relative dream to shoot. The Bowtech Allegiance would be a perfect example of this.