Overall service was average. Little time spent with customer, didn't have confidence work would be done on time per scheduled service, the final invoice wasn't clear on whether cabin filters were replaced as part of the intermediate service, and the agreed upon discount over the phone wasn't completely honored (phone discussion referenced 15%, but only received 10%). At the end of the day, 5% discount to your customer base is probably meaningless, but more importantly, stated matters should be remembered and honored.
Seems like the shop is trying to pack in a lot of volume....suggest to slow down and spend some time w/ customers, The type of folks that bring their cars to you are probably the type that care more about the car itself so it goes a long way when the shop shares the same appreciation (or at least appear to share it)....rather than just to bring volume in, say "hi, thanks for bringing your car in"....and then here's your invoice and "come back again".
I've given you guys 3-4 opportunities, even after damaging my wheels on a simple tire replacement....I don't see a lot of potential to significantly improve the overall service and experience and suggest management to seriously evaluate how the shop is running as there's plenty of Porsche service providers out there....especially here in SoCal...good luck!