I'm sorry, but the first thing I did when I bought a pair of used CT-12b's was inspect, spin, and check for shaft play and clearance to housing. When you buy a used turbocharger, what are the things that people stress THE MOST? Not cleanliness, not warranty, not how shiny they are - I believe the phrases "Spins freely" and "Minimal/no shaft play" are what you want to hear.
Also, to imply that something dishonest could not have been done on the buyer's or buyer's mechanic's end is ridiculous. How easy is it to get your hands on a used CT-26? Now, over the course of a year, how easy is it to get your hands on a customer's freshly rebuilt AND UPGRADED turbocharger, one that fits on a car that you know a lot about? I'm not saying that the mechanic is crooked, or that the Supra he owns is even a MkIII, but how easy would it be for a mechanic that works at a turbo shop, over the course of a year, to get a crap CT-26, clean it up, do a crap job "rebuilding it" and give the old switcheroo for a CT-57 that was done right? That sounds like a crazy story with too much coincidence, doesn't it? Slippery slope? There is also a lot of coincidence going on, what with this car rebuild lasting well over the warranty period, having an improper installed/primed turbo, which was never run, but was driven once, with a "crap turbocharger rebuild" that was out of warranty and disassembled by the same shop that churned out this crap turbo which made a car into a smoke machine.
What I've seen in this thread is ridiculous. IF this turbo came directly from Jon and was put on the shelf, and never touched, and then was found to be bad later and it was within the warranty period, I could see someone having a case. For this item to never have been changed, molested, disturbed or otherwise messed with over the course of a year, and then magically it's total garbage - well, that seems fishy to me.
Lagged, you play devil's advocate WAY too often.