I'm sort of thinking you're referring to KOs, not 3rd party transformers.

off the top of my head I can remember more official transformers that people have broken on the first transformation than 3rd party ones.
Masterpiece Rodimus and Masterpiece Megatron. The former was fixed, the latter was not.
Not to mention Universe Galvatron who loses a limb if you enter the room the wrong way. Had quite a few repaints, never fixed as far as I know.
The list is much longer.


Hercules had two significant problems, Heavy Labor's waist ratchets and Mad Blender's combiner knee, but they've shown us how to fix that.
MMC Knight Morpher Commander is the only other one I can think of with problems, but they were fixed in a later release.

I guess Impossible Toys Arcee and BTS Sonicron should be mentioned as well, but they were their respective companies first transforming offerings as far as I can remember. (Just like MMC KMC and xovergen STC actually)

Does Has/Tak has a perfect track record? absolutely not.
Do 3rd party companies? No.


Edit: aaand Ceasar121 said pretty much the same thing. I really should read all the posts before replying  

 

Their superior design and detail quality is a fact. QC issues happen with anything.

 

I already have a spot for all of them. XD