Now that it's out officially, to me, this is like a... B-level execution?
Rear end looks like the CLA and the front/side could be literally any Mercedes sedan over the last 10 years. If Lexus did this, they would be roasted mercilessly. The exterior is wholly unspectacular looking, which is a bit surprising following two generations of fairly bold S-Classes (W222 and W221) that were style forerunners for the rest of the lineup. I can see the shape looking more svelte in person, but from pictures, the car has virtually zero presence or personality. I'm not sure if this was a brilliant move by Mercedes in an effort to not upset what works, or if the car will age poorly and struggle for not looking "new" enough.
Interior? A mixed bag to me. The dash looks gimmicky and like the Las Vegas strip with lights, textures and screens everywhere. The seats and door panels are absolutely beautiful and look very premium, but I really dislike the dash.
Powertrains are awesome, which we've come to expect from Mercedes at this point. After the rumors that the V8 was being dropped, I'm glad to see it in the lineup.
LS definitely has more presence from the outside. Interior is probably a tie to me - I dislike the dash on both, but everything else is nice on each. Mercedes obviously has the upper hand on powertrains.