Just yesterday, I scheduled drive unit replacement at Service Center. I was explaining to a friend, and having to articulate made me think about how much better this really is. Rather than repair unit at service center, Tesla's current policy is - regardless of magnitude of problem - swap entire unit and send back to intergalactic to be inspected and refurbished. This offers far better corporate insight into root causes, accelerates continuous improvement of design, leverages a small number of experts, and allows for better quality control. Not to mention the very positive customer service implication: 4 hour procedure vs. many day procedure. I tried to make analogy of ICE engine. What if every time you needed rings or a head gasket, or a timing chain, instead they just pulled the engine, put in a refurbished one, and sent yours back for inspection/repair? Well, of course they could do that! Having worked as a mechanic, I know that - in many cases - pulling and replacing engine takes less time than taking it apart and fixing something. And, it would offer the same QC benefits. It just isn't done! And, it's not because the goofball at your local shop is really super-proficient at replacing rings - he/she may not be! It's because the dealer model would never support this. Dealers make their profits from repairs, so they HAVE TO do this locally. Unless the manufacturer offered them a bounty on each engine they sent in, which would render the whole thing economically infeasible. So, this is another huge improvement in quality and service that has nothing to do with the technology (could be done with ICE drive unit as well), but is enabled by the delivery/service model. As I say this, I have to note: I was told at Service Center that Tesla is in process of rolling out a procedure for Service Centers to fix certain drive unit problems - just as they now fix certain battery problems. It is possible that the logistics costs of the central repair model are unsustainable. Or, hopefully, they are going to hold this to "certain" diagnoses of known problems, so they continue to get the leverage and quality that comes from the central model.