And it's a step I'm not sure I'm comfortable with. Audi's system, as featured on the new Q7, has a feature that uses the forward-facing camera to read speed-limit signs, something that's becoming common in Europe and is now making its way here in the continent's luxury cars. That part's fine; it's useful information and gets nicely integrated into Audi's Virtual Cockpit screen and on the head-up display. What the car then does with that info, however, is the issue: If your set cruise speed is higher than the speed on a sign you pass, the car will drop the cruise speed down to the limit.
But it's not perfect. On one stretch of highway, the Q7 picked up the speed limit posted on the parallel service road, dropping me down from a little above the limit to 30 mph. It didn't slam on the brakes, but it did confuse me at first and require intervention before the car slowed down to a crawl. This feature isn't ready for primetime. Luckily, it can be turned off or switched to a mode where it gives you a warning that the speed limit has changed (or at least that the car thinks it has) and lets you react before the set cruise speed is changed automatically.
When activated, it's a safety issue. A more serious one, in my opinion, than driving a little over the speed limit, especially when it means interrupting the flow of traffic. There's nothing predictable about a car trundling along in the fast lane and then completely letting off the gas. It's not predictable for the driver behind you, and it's not something a driver expects of their own vehicle.
Yes, this feature was obviously developed for people driving on the Autobahn, where speeds can drop down from unlimited to a slow crawl pretty quickly when entering a construction zone or approaching a built-up area. German roads also have more consistent signage, so the false-positive scenario I experienced might not have come up there. People don't speed in Germany because they generally take driving more seriously, gas is expensive, and the unlimited stretches allow those truly in a hurry to make up time. But in America, this speed intervention doesn't make sense for most people.
Like all active safety features, active cruise continues to improve, but this feature within a feature is one I'd leave disabled for the sake of safety, not despite it.