Both cars scored well in the four major areas that Euro NCAP tests - adult, child and pedestrian protection and safety assistance systems. The E-Class scored marginally higher than the 3008 in the last test, because it comes with Autonomous Emergency Braking (AEB) as standard. AEB is a key safety technology that can automatically apply the car's brakes if the system detects an impending crash. AEB is optional on the 3008.
However, despite the E-Class's high scores, safety group Thatcham Research says that more needs to be done to make important safety systems standard equipment - for example lane departure assistance, which warns the driver when they're straying out of their lane. Some of Mercedes' most advanced systems, including its semi-autonomous driving functions, are only available as optional extras - and less than 10% of buyers typically opt for such features.
As What Car? research has previously shown, drivers in the UK are four times as likely to specify connectivity and media upgrades than additional safety features when choosing their next car.
Got a motoring question? Our experts are standing by to help, just tweet us your question using #askwhatcar
For all the latest reviews, advice and new car deals, sign up to the What Car? newsletter here