This small gallery points out the color differences between Universe and USA Edition (what the Japanese are calling their version of Universe Ultras).

http://www.tf08.net/forum/viewtopic.php?f=3&t=29

The Japanese Onslaught is certainly much more G1 accurate in color shading but the Hasbro one is still very good. I don't really see enough difference here that would obviously make one figure better than the other unlike many of the deluxes. It's just a matter of taste.

BTW: The USA Edition robot head is to be painted considerably different to Hasbro's for a more G1 look, we have seen blurry pics showing this so far but no Hi res to see the detailing.