@BigDave Interesting about your Mercedes, as I had exactly the same issue with a new Mercedes GLB hire car last year. The digital dash went completely black on the first day that I drove it. I had absolutely no idea what speed I was doing, which is no defence if stopped for speeding! The car also went into ‘limp home mode’, where I couldn’t go above 10mph unless activating kick-down, which cancelled it. I had the car for a week and the dashboard went black on two further occasions. I battled on with it as the previous two hire cars had been a Vauxhall Mokka and an MG HS which were undoubtedly the two worst cars I have ever driven and I didn’t fancy getting one of them again!
My late father never liked lots of ‘gadgets’ on cars as his view was it was “more things to go wrong”. I don’t share his view as I like my tech, but I’m no fan of digital dashboards as you are left high and dry if they fail. All the more reason to do as BionicRusty is doing and buy a car that is a few years old, as they don’t have these things and any initial glitches have been sorted!