Hm, I also remember people asking about this when they wanted to make a hero from a unit. But I don't see many weighty reasons to import both models because who the hell needs the same looking model as a hero
and a unit in one map? That just doesn't make much sense because the hero is a more important entity, which should be very different from a simple unit in appearance. Only maybe if it's some sort of an RPG where a unit becomes a hero
Well, and technically it does have drawbacks such as poorly placed or missing attachment points on some models, things like glows that are the wrong size, and ill-shaped glows when it comes to oddly shaped weapons like scythes, longswords, or halberds. And some other things, like you don't see the glows in the editor or they contain only one square plane with one billboarded bone and cannot create enough volumetry. In this regard one will need many different types of glow, taking into account their shape and size, so that everything looks rather warcrafty.
No matter what anyone says, but for me there is nothing better than a completely self-sufficient model that is designed to be a unit or a hero with carefully adjusted glow that you can observe in the Sanity or in the preview