Ok I feel l need to log my AP 8.0 experience here. Apologies in advance for the long post.
I have had my MS90D for 3 months..and logged just under 3,000 miles. I have absolutely raved about this car and (at least until 8.0AP) have loved nearly every minute in it...coming off back-to-back leased 750is and a number of other similar vehicles prior to those.
Last week I did a ~1,000 mile road trip...something I would generally not do...especially as a 20 year instrument pilot (yes, I know how real autopilots work). But I love driving the car and AP takes the overall workload and related stress of the drive down a lot, so I decided to drive it.
I did the outbound leg on the latest 7.1. It was AWESOME. Pretty solid tracking, NO scares whatsoever...and very reasonable 'nags' (in fact only a couple the whole trip). Absolute best long distance drive I've ever experienced.
I was pleased to get 8.0 during my stay and was looking forward to putting it through it's paces on the way back.
Well... Let's just say that I thought of two new bumper stickers on the way home: "My Tesla Loves Semi's (so much it wants to kiss them)" and "I'm not drunk, I'm on Autopilot 8.0." I literally thought that if it didn't throw itself (and me) under a semi, it was going to at least get me pulled over. Really very disappointing.
(I'm not going to go into the 'nag' thing. I get that it's 'beta'...and that you'r'e supposed to have your hands on the wheel at all times, etc. etc. I WILL argue the point that you should not be penalized for looking at the road (and not the dash) and leave it at that. Overall my experience on that front hasn't been 'terrible', but it is a decided step backward for me.)
The big issue for me is tracking, especially passing semis. Unlike many people experiencing 'better lane tracking', I have experienced quite the opposite, and it sounds like others on this thread have as well. And I have talked to other friends, including one on his second MS, who have had similar scary issues.
Before 8.0AP I only had a couple (maybe 'several') instances where I needed to quickly take over from a situation where I felt like the car was about to get me into serious trouble. On the way home it happened numerous times. Not tracking well, weaving back and forth/'seeking', hard swerves...especially cresting hills...if you can even call them that (this trip was between florida and atlanta). I did get one minor 'phantom' brake incident, but I didn't register it as a big deal.
The real dangerous thing was it pulling hard into many (at least half) of the semis I passed. Some trucks induced the behavior and some didn't...I have to guess it is related to aerodynamics/buffeting of the particular truck and how AP is trying to deal with that. I only pass semis on the left...so this was always on that side. I assume the behavior would be the same on the right.
Sometimes it felt like an increasing oscillation, others it just felt like an abrupt pull to the right. What was even scarier is that it really felt like the side sonar wasn't doing (or going to do) anything about it. Perhaps it would have, but I didn't feel like letting it go far enough to find out.
Sometimes I could hold it off with SOLID left pressure on the wheel (right up to the edge of disengaging). Other times I had to force off AP, a couple times pretty aggressively. On 7.1 I do recall it often hugging the lane next to a semi closer than I liked, but I don't recall it ever pulling into one anywhere close to this aggressively.
Beyond that, I still feel like AP isn't tracking as well as it was before, even in stop and go. My wife commented on it during a drive last night as well. I just engaged it going to lunch and though it was going to sideswipe the car next to me.
I DO feel it handles AP accel/decel/braking better than before.
I love my car and I support Tesla and what they are doing on a number of fronts. I am not bashing at all here..and I am sure as heck not making it up. I love how they push forward and I am willing to fully understand the limitations of my vehicle's systems as 'Pilot in Command'. I am holding out faith in their agile development processes, OTA updates, and fleet-learning capabilities to get this at least back to where it was before…hopefully quickly. I hope that's not a naive position.
At the moment, at least as it relates to AP, I wish I was still on 7.1.
I am sure that others have had different/better experiences, but that is my experience...please don't flame me for sharing it. I'm just trying to be helpful and add to the dialogue and the record.