I have FSD and owned my M3 for the same amount of time. With FSD you get Navigate on Autopilot that handles lane changes on the highway. It has the same issues you see. The lane changing isn't great, it wants to change lanes more frequently than I do and will often try going into the fast lane even though there is significantly faster traffic coming that I would be slowing down. I often have to disable navigate on autopilot to keep it in lane because it will suggest changing lanes, I'll cancel, then a minute later it will suggest it again.

I'm hoping once the two stacks are merged, that will improve.

The other problem I have on high ways is I can't really use it in stop and go traffic. If I do, it will frequently accelerate to fast from being stopped then have to break hard when traffic reaches a stop again. Too jerky for my comfort.

Overall, when I can use it, it makes driving less stressful. I drive 600 mile round trips a few times per year and am able to have it engaged vast majority of the time on highways.

FSD Beta on city streets requires too frequent overrides for it to be anything more than a party trick at the moment. Even in very rural areas it will have problems of either not changing lanes when it should or changing lanes when it shouldn't.

Auto parking worked great for me initially but something changed and it is never able to detect parking spots for me. The few times it does it just flickers on the screen then disappears, resulting in me not being able to use the feature. I'm not sure if this is because of a problem with sensors or if it's related to me being in the FSD Beta. I've been in the FSD Beta for over a year now.

> The other problem I have on high ways is I can't really use it in stop and go traffic. If I do, it will frequently accelerate to fast from being stopped then have to break hard when traffic reaches a stop again. Too jerky for my comfort.

110% this.

In addition to this, I often find that it is a bit timid on the acceleration once traffic starts really moving. Like, it'll jerk a bit forward from a stop, but then veeerrryyy slllooowwwlllyy speed up, even once traffic ahead is over 100 feet away.

Something interesting to me, as someone with a 2020 base-level Forester, is that you describe my experience completely. It works great on most highways, but needs me when lanes split or merge.

Of course it's not 1:1. AP has other features, such as a much nicer UI that better reports what it thinks it sees, and I think has sexy lane changing features and such.

But it makes me feel that FSD was more business necessary to keep a competitive advantage against cheap cars. Soon many cheap cars will have AP-like features at comparable fidelities.

I have the exact same experience with AP. I trust it on highways until a merge or lane split is ahead. I think it's so silly that the decision making isn't more robust..

If I can't trust AP with simple road rules, then why bother upgrading to FSD?

FSD handles road rules significantly better: the road up to my house has a complicated five-way intersection with a railroad crossing that EAP could never handle. FSD navigates it perfectly. For my 40 minute compute, there are about three spots where there’s predictable road issues that force me to disengage (no safety issue, just the car gets really hesitant) but otherwise it’s obviously an upgrade from non-FSD.

> I can say that I've never had to disengage AP because of imminent danger, though I HAVE had many times where the lane is splitting and AP can't decide which way to go, so I had to take control.

This suggests a trivia question, which I do not know the answer to: what lane in the US goes the farthest without a split or dead-end? Similar question for other countries.

I'd count most freeway exit ramps as splits from the adjacent lane, but would not count intersections with cross streets as splits unless the two roads intersect at a small angle. It is the actual lane that matters, not its name, so if a lane has a name change when it crosses some political boundary it still counts as the same line.

My first guess would be it is on some long freeway like I-10. My second guess would be it is on some rural road through the middle of nowhere.

US is surprisingly bad at this though: in Germany, you get on Autobahn and you know the lane you are in is going to go forever. In US you get on a highway, get to the leftmost lane, it gets to the city, you driver straight and suddenly find yourself in the exit lane on the right? Who designs highways this way?!?!

> This suggests a trivia question, which I do not know the answer to: what lane in the US goes the farthest without a split or dead-end? Similar question for other countries.

I-80 starts in San Francisco and ends in New York City, but I'm certain there are splits that would make you change to some other highway if you stayed in the left lane.

Likewise, I-90 starts in Seattle and ends in Boston and travels through Montana.

My guess would be I-90, just because of Montana.