Revisiting this thread after a quiet couple of years here, prompted by a pleasant SC experience there last week (and another great one last summer).
This is a VERY busy delivery and service location - I would so far as to they have objectively outgrown the real estate footprint (and they are using the outer portions of the QuakerBridge Mall parking lot to stash sometimes hundreds of vehicles waiting for delivery). My only complaint about my service last week is that the instructions in the app told me to park in a spot across from the service bay, but all spots were taken, there were vehicles parked in the entryway (blocking other vehicles in the service spots), and I got the literally last open spot in the sales area at the front of the building. I also had to wait close to two weeks for my appointment, but it was a minor issue and the wait was OK.
Last summer (2021), I think a couple days before July 4, my 12V battery died and I woke up to a totally bricked car. It was towed to Princeton SC and showed up unexpectedly, and they worked me in on a holiday weekend while they were understaffed and had me out of there in less than 2 hours. Earned a lot of goodwill with me that day.
Another good experience last week - they offered me Uber credits, but estimated the work would be done within a couple hours so I opted to wait in the showroom. Did a work meeting on high-speed/high-quality WiFi, sat in the Model S Plaid in the gallery for a few minutes, and when they came to get me (after just 90 minutes) they reported that they were able to resolve my issue without needing any parts, and I got out of there for free. (Issue was a slow leak in a tire - I feared it could be a puncture, but turned out to be a loose connection to the TPMS, which they tightened up and has been stable since.)