Holy smokes!

You have your production pieces which probably pass the Q&A process of, if it fits, its good! looks don't matter.
Then you have your replacement parts, made by someone else with a different machine, obviously, and pass a rigorous Q&A process!

I am almost afraid to take mine apart! But I won't do it till there is a problem. Mine is still trying to finish off its second gallon! @40, 10 minute flights so far.
Runs reliably!

Mike R