Several weeks ago I traded in my 12/2014 P85D(L) for an inventory P100D with a 1000 miles on the odometer. Before hand I had posted and asked if people thought that there were any improvements in fit & finish between 2014 and the newer car, with most posting they had not perceived any improvements. My inventory car was delayed in shipping and I was fortunate enough to drive several 2017 inventory cars for further comparison to my 2014, and to me without a doubt, compared to at least my car there have been significant improvements. Firstly, I had a lot of issues with my car, so your mileage may vary comparing a similar 2014 to a newer car. The main reason I started thinking about the trade was due to all the issues I had with my car. I figured as with anything it would not get more reliable with age. Some of the issues I had were minor and others were more significant like leaking front motor, windshield layers delaminating, repeated front suspension problems and I could go on and on. I loved driving the car, and thankfully service was outstanding despite having no local service center at the time. These are the improvements to me: Doors - Firstly, after driving my car and the several new inventory cars, I can tell you that the door seals seem dramatically better. I have noted that with the newer cars you need more force to close the door, and when closed and driving there is much less wind noise than I ever had in my car. Not only for myself, but my teenagers and wife were each surprised on separate occasions because the typical force to close the 2014 door would leave the door slightly ajar on the 2017 cars. I looked at the seals and can’t tell any difference from looking at them, but they are definitely more effective sealing. Sunroof - The P85D had sunroof version 1.5 and new cars are coming with version 3.0. I had a lot of sunroof issues and multiple service visits from the metal tab hitting, to not sealing, squeaking and ultimately needing to be replaced. Even after it was replaced it sounded like it was open until they found that there hadn’t been adhesive installed all around the sunroof to hold the rubber seal. Well, opening the 3.0 sunroof on the new car is awesome. It just opens, exceptionally quietly and smoothly without any jerking, or popping. I was considering going with the all glass roof, due to all the problems I had had, but really like the open air feeling on mild days. Glad I went with it. When the 3.0 sunroof is closed it is as quiet as the glass roofed inventory cars I drove. Front suspension - Even after the multiple repairs I had on the front suspension and being told that everything was in spec I would get a lot of significant noise with turning. I particularly noticed it at low speeds, and when backing up in parking lots. I wondered if it might have something to do with the 21” tires. I can tell you that the P100D with the 21” is absolutely quiet. Motor Noise - even when new, and also when my front motor was replaced, I would notice a lot of motor noise. Additionally I had a pretty audible oscillation noise that would be there anytime the motor was at 77 mph, which unfortunately is a normal highway cruising speed for where I am. I did several test drives with my local lead tech who stated that was normal. On the P100D there is no oscillating noise at any speed, and there is barely any discernible motor noise at all. Performance - My P85D was a 12/14 delivery and came with the suspension plus, and splitting hairs I think that in the corners the P100D feels a little more “pillowy” and less rigid. As far as acceleration when I upgraded my P85D to Ludicrous I thought, “man this is how the car should have originally come.” The passing speeds, and acceleration onto the highway seemed more frantic. Well, on the P100D I have not been hammering the car off the line, but passing acceleration is on a whole other level, even compared to the P85D. The acceleration just seems effortless at any speed, it almost makes the car feel telepathic. You are thinking about passing, and then you are. Fit & Finish - I know that this is subjective, but I got to compare it to the several inventory cars I got to drive. To me the newer cars felt unquestionably more solid and better put together. There were not all the creaks that I had in my car from day one, the motor was not making all the noise it was, there was not all the wind noise at highway speeds. I really feel like I got to finally experience the pleasant quietness that other have reported. Sorry for the long post. I was hoping it might be of benefit to some.