I love our 2017 Outback w/ EyeSight. Luckily, we haven't had to test the auto braking system at high speeds but the lane assist and assisted cruise control are wonderful.
Not a suburu but my passat engaged emergency breaking once. It's was kinda spooky to go for the break and realize its already depressed. Definitely prevented an accident. I was paying attention too, but someone jumped into my lane and slammed their breaks on for who knows why, there wasn't anything in the road...
In some areas that maneuver is a strategy to collect an insurance payout. If the car had many passengers (who would all get soft tissue injuries) this might have been a "swoop and squat."
> someone jumped into my lane and slammed their breaks on for who knows why
Insurance fraud, possibly. Depending on jurisdiction if you rear-end someone you could automatically be 100% at fault (assuming the fraud is not discovered/proven)