Some differences are:
It comes with a second head.
The crane is detachable.
The upper arm connectors are longer to get rid
Of the stubby arm look.
The crotch piece of adjustable so the legs have better articulation.
Improved connector ports and locking sections.
A foot stabilizer for not scrapper.
And the crane and gun can combine to form a giant melee weapon...I may have forgotten something. lol.