I have had a 2017 MX for a couple of weeks, and have been testing the AP for a reasonable amount of motorway and highway travel.
My feeling is that for LH driving (New Zealand) it really has a long way to go before being safe/reliable. Perhaps it is better in right hand drive environments?
Here's my findings:
- The car seems to hang slightly to the left of middle of the lane and wanders around. If you are in the right hand lane (the fast lane), you really want to sit slightly to the right. Otherwise you are really close to large trucks you are overtaking, and given both you (the tesla) and the truck wander quite a bit, there is very little room for error. I usually grab control just before passing anything large.
- As someone said previously, it is a *long* way from being safe on undivided highways (i.e. where there isn't a barrier). It wanders around, and even had one wheel completely over the middle line across the rumble strip and towards the oncoming traffic around a gentle corner before I grabbed it back. This was a well marked road.
- Anything at all confuses it... road repairs, old paint, bridges.
- It really seems to hate cones off to the side of the road, and drives at them. Similarly vertical strips (used beside the road sometimes) sends it all over the place.
- Bridges are very bad - here the guard rails tend to start wide of the road and become more narrow - kinda like this
http://www.newzealandnz.co.nz/wp-content/uploads/2014/09/Small-Town-New-Zealand-South-27.jpg. but with a wider 2-way road. Even when the road and bridge are clearly marked, the car steers straight at the bridge entry wall. Its not even trying to stay on the road.
Sadly - bug reporting seems broken in my car so there's no way to report this stuff. I can use the audio "Bug Report" command, but it just says "Thanks". I can't even report the bug in the bug reporting software.