2/5 because it's the only converter I know of. 3ds files worked on 2 out of 3 models which is great, 1 crash.
Textures needed to be vertically flipped but they work, also great.
Problem is they dont open in War3ModelEditor or work in WC3 without further processing so I'm having trouble thinking of who this tool will benefit. People who can't import OBJ or 3DS files to their program but can open half-broken MDX files? Not sure a program like that exists. I tried converting the mdx to mdl with another program but it wigged out and turned the 42kb mdx to a 1.2gb mdl. Tried MDX squisher, didn't crash but didn't fix. I can't speak on animations but I imagine they wouldn't work. It's clearly converting them to MDX but not in a way that WC3 etc can recognize.
It "works" for OBJ in WC3 and War3Editor but every model I try ends up with broken geometry like this
Can be fixed with some autofilling but it's tedious and doesn't apply to the texture so textures effectively don't work this way.
I'm no expert but the OBJ converter part isn't a viable option for me either. Good attempt and
if improved can be extremely useful.
I use Blender so all non-wc3 tests were done in Blender.