My S85 went in for the driveline replacement yesterday, so I got a service loaner. Fortuitously, it was also an S85, allowing me to make some back to back comparisons. A lot of this is old news, but some of the little differences were interesting. The new car has greater resolution on the parking sensors (meaning that the arc of the sensors is broken into more segments), and a broader sweep of coverage. It also seemed to be a little less alarmist about activating the "OMG Stop"" chime. The newer stalk control layout is generally quite nice, especially when it comes to the turn signal and cruise controls. OTOH, I thought that the shift lever was actually a step backward; by making it symmetrical with the stalk on the other side, they've made it seem more like the wiper stalk you'd find on most other cars. I'd rather have something like the old design that more clearly stands out as having a different function. The black alcantara headliner is nice enough, but it kind of makes the car feel like a cave. It may have been just me, but the hip point of the seats also seemed higher in the new car--these were the stock seats, not the "next gen" units. It felt like I had less headroom in the new car. The taller rear set headrests are extremely annoying, and make rear visibility (which already isn't great) substantially worse. I wish those could be folded when not in use. Lane departure warning is...a feature. I suppose it's helpful. Mostly I found it irritating when I clipped the apex on on and off ramps. I don't know why anyone wants a self-driving car, though, so I am the wrong person to ask about its merits. The iBooster brake setup is a mixed bag. It definitely has a more uniform, consistent feel, and it makes the old vacuum booster in my car feel spongy by comparison. Nevertheless, it also feels overboosted and touchy in parking situations, and the release of the hill hold function comes through the pedal in a more obtrusive way than in the old car. I'd say I probably prefer the new system overall, but it's not a slam dunk. The newer car had 21" wheels, which continue to look the business, but my time with the car confirmed the wisdom of ordering the 19s. The 21s have substantially more impact harshness; any improvement in handling, turn-in, or steering feel (if it exists) was imperceptible to me in street driving. If I keep the car long enough to need new tires, I'll keep the 19s and go with a slightly more aggressive set of summer tires.