With FSDb 12.3 believes the speed limit on the 55mph highway nearest me is 10 mph. This seems to annoy the folks who want to go 75 or 80. One of the passing cars cut back into my lane with a good 2" of clearance. When it sped off down the road, my car zipped up to 92 mph then back to 83 for a while then slowly drifted back down to 10, so I had to hold it at something reasonable with the accelerator pedal. Initially, the accelerator seemed to have no effect at all, but after mashing about on it for 1/2 mile or so, it began to allow me to set the actual speed that way. Initially was pretty scary when it didn't work at all.
It is still doing the "turn right in 1,000 feet", dive for the left lane, 1/2 there hold and think about it, then at the last moment, dive for the right lane and do the right turn and vice versa for left turns. It's certainly better than it was, but plenty of room for improvement yet.