Nobody said it was slapped together on the fly.
It was copied from the original, The chinese manufacturer has a vested interest in making it as close to the original as possible.
Some console manufacturers are even starting to discuss not writing libraries for fixtures from this and other chinese knock-off manufacturers. So the MS lighting must make the fixtures as close as possible to the "real" version, or they may be left out in the cold when nobody will write a profile for them.
And as for your "drive through window" If you buy from a reputable source, they will be more than happy to help you with any problems you may encounter. And even repair units under the standard factory warranty.
I don't think you will have any luck getting warranty service from MS Lighting, much less parts.
On a side note, Lets speak hypothetically here.
Say somehow this fixture starts a fire that causes property damage.
When the fire marshal figures out that this fixture caused the fire, and it is not UL or CE listed, YOU are going to be the one responsible for the damages.