Mercedes has some interiors I really like - like GLC and C class - but some I can't stand, and strangely, it's generally their flagship cars I dislike so much. The S Class's column mounted shifter reminds me of a Crown Vic, and the shape of the steering wheel + circular vents has never really worked for me. Mercedes talked a lot about this new GLS finally being the "S Class of SUVs," and I just don't get that vibe.
GL/GLS has always looked like a big Highlander with nicer details, so the exterior design is nice but not particularly imposing or elegant. It's fairly basic, in my eyes. Mercedes design was great with the S Class, C and GLC, but now E, GLS, GLE and CLS are all looking too much alike with no real differentiation aside from size. Not my favorite.
On top of that, this layered dash with a large tablet that looks to be sitting on top of HVAC vents gives me vibes that are equal parts "Starship" and "unfinished integration." The other details look nice though. Mercedes is a big fan of just dropping framed screens in different places and it never looks well integrated or polished, IMO. Lexus does a much nicer job with integration on vehicles like LS, LC, LX and even ES. Even RX seems better integrated.
Another thing I'm seeing more often and don't understand: grab handles integrated into the transmission tunnel or dashboard. Why? What purpose does this serve? It seems like a completely unnecessary design cue that would only get in the way. Porsche has it, as does the LC.
Engines are great, as always with Mercedes.
I feel like this is 6.5/10 for me. It gets the job done, but it doesn't give me the warm and fuzzy feeling that a Mercedes flagship vehicle should.