There are some differences between a legit G1 Swoop and the KO, but it all depends on what the individual is happy with or willing to accept.
Below are the main differences -
* Factory applied stickers are not applied. They come on a sticker sheet instead.
* Toy itself is relatively low quality. Soft plastic was used, the toy doesn't fit together well, and it's generally lose.
* The red paint on the diecast chips very easily.
* The head it comes assembled with is not painted. Subsequent runs included an extra painted head in the package that can be swapped out with the unpainted head.
* Some of the initial run comes with Grimlock's sword instead of Swoop's sword.
* The launchers do not fit on one of the wings.
The above does not include comparisons made between a legit MIB Swoop and a MIB KO. See
here for a detailed guide.
Personally, I do not care how someone goes about their collecting or make any moral judgements about anyone.