I have used cross cut sleds and miter sleds for many years but never had a bevel cutting sled.   Bevel cutting sled does the same job as miter sled.  However, the length of miter sled cut is limited to the height of table saw blade, while a bevel sled cut is limited only by the size of the sled.

Found the bevel sled made it easy to make a mitred corner box that went together clean and square.   

Properties of this sled that contribute to precise cuts:

1. Fence on the miter sled was calibrated by 5-cut method to get it dead square to the blade.   
2. Stops on the miter sled fence ensure that the length of box pieces are exactly the same.  
3. Clamps on both fences keep the material flat on the base during the cut.
4. Tight fitting UHMW runner eliminates any play between the sled and saw table.

Video showing construction of sled and how to make a box using the sled. https://youtu.be/ZtD9_vgMeAc