Besides a few possible 50,000+ mile examples, Tesla Model Ses are all in warranty right now.
Once they're out of warranty, it's possible that customer satisfaction will go right out the window unless Tesla subsidize the cost of repairs further.
Tesla seem cognizant of this issue in that they both offered a better-than-standard warranty for their market segment and are proactive about updating cars to revised parts (as opposed to other manufacturers, who often force consumers to harass dealers about service bulletins they've noticed and want fixed).
However, I'd still worry a bit. Systemic issues could result in increased depreciation and a tarnished reputation, which would be a double-whammy for Tesla thanks to their aggressive buy-back lease program.
Plus with a complete vendor service lock-in, Tesla are in complete control of service prices and availability. This is a tricky game to play. Right now, Teslas are relatively expensive and owners probably won't have problems paying dealer service prices, but as Tesla move downmarket they'll have to strike a balance between making a profit and preserving their reputation, and there aren't any third-party mechanics for budget-conscious consumers to seek out.