There's actual differences in the toys too. Most noticeably with TAK Convoy (full length smoke stacks, "clean") vs. HAS Optimus Prime (shortened smoke stacks, "scorched") and TAK Starscream (green, inferior plastic) vs. HAS Starscream (G1 colours, better plastic). Differences between the HAS and TAK versions of other MPs are not as significant IMO, but they do exist.