I think you are missing the point — most companies have similar things… generally the repairs by a 3rd party are not that great but people get them done because they are cheap or their product is out of warranty…
But if you look at any security company, whether it be alarms or safes etc, only certified members can repair the security products – if it is detected that a 3rd party has messed around then the security company will say the system has been breached and often wont touch it…
Apple have openly stated they are serious about security — this “error 53” is in place to stop people tampering with your devices – for all you know, this 3rd party person could be fitting an apple lookalike touch ID button that allows them to copy your fingerprint and access your data — worse is that they could fit a cheap copycat version of the button…
As for replacement batteries — will you complain to apple is the cheap replacement starts over heating and affects the other components — there is a reason why most companies, and customers, don’t want people tampering with the device…
My iphone 5 was almost 2 years old and due for an upgrade, the battery started expanding (which can happen to any battery) and the apple store replace the whole device for free because my device had not been tampered with — had i got a 3rd party to look at it first, then took it to apple, they wouldnt have be legally bound to do anything.
Plus – if you are going to have an expensive product – make sure it has cover and/or extended warranty!!!
Die Fingerabdrücke vom Besitzer ziehe ich nicht aus einem verschlüsselten Chip, sondern 