The Jets just have the flat along the edge serrated versus the edge and chamfers that Bessy uses.

That said, I do like the Jets. They are clunky compared to Bessys, but have some nice extras.

Locking lever to keep the movable jaw from sliding when using vertically.
Threaded holes in the heads for mounting to a table or other uses.
The supplied stands slide along the bar and have a thumb screw to lock into position, also their base has a threaded hole for securing to a surface.
The handles are large and hexagonal for a much better grip and more leverage.
Higher clamping force IMO.

Basically some things Bessys could use, but they'd need to add them without adding the Jet's clunkyness.