Recently purchased a 2018 Mercedes-Benz E400 4matic wagon with premium package 3 that includes all of the available driver assistance programs (semi autonomous steering, adaptive cruise control, lane keep assistance, blindspot detection, automatic parking assist, cross traffic alert). According to Mercedes, the program titled drive Pilot with steer assist, is able to keep the vehicle in the lane when there are lane markings or even follow a car ahead if there are no lane markings. Well, this system is terrible. It can't stay centered in the lane, instead it feels like you're playing a game of pong going back and forth between the lane markers. That is, when it works. When it doesn't work (most of the time), you will be going down the road and it suddenly starts drifting out of the lane to follow the curve of an off ramp or it suddenly disables itself because it can't figure out where the lane markings are. There's no audible warning or big visual cue the steer assist has ended, just a tiny little steering wheel icon in the head up display turns from green to gray. Mercedes advertised this system to be better than or at least on par with Tesla's autopilot, yet it can't read stop lights, can't even stay in well marked lanes and combined with the adaptive cruise control that has no way of changing how quickly it accelerates, feels like the car is out of control. What I find even more disappointing is that the Mercedes apparently will not be given software updates to improve the system unlike Tesla who is constantly providing their vehicles with over the air updates. If Mercedes can't do ota updates fine, but they must update these cars are the dealers. I feel like this system desperately needs a software update to be even marginally functional. Dealer has no clue about these issues because our car was one of the only ones ordered with all of the assistance programs.

- Raleigh, NC, USA