My wife and I and a friend did a test drive today in GT, AG, Tahoe, 21/22 wheels, no HUD. Here are my honest observations and take away:
Seating/steering position: The Gravity seats you higher in the vehicle than what I'm use to in our EQS SUV (we've owned our Mercedes for 3 years so the Gravity for us is being measured against our EQS SUV.) I did not care for how low the steering wheel is located compared to most other vehicles including our EQS SUV. It felt like I was steering from my lap. I did have a good view of the cockpit display but at the expense of an oddly low position for the steering wheel. I didn't care for the steering position.
Screens: The cockpit display is very nice but it could be brighter. Our test drive was in bright sunlight and it looked washed out at times. The lower screen looked fine, even in bright sunlight.
Wireless phone chargers: both chargers worked in our tester. Even the SA was surprised as he told us they were not yet working. He said the service people were working on them and must got them working.
Regen: I drove mostly in Standard Regen mode which was odd for me since the EQS comes a setting called Intelligent Regeneration which allows the car to coast but will auto brake via region if a slower car is in front or you approach a stop sign or a cross-road. The one pedal driving works as expected in the Gravity but I prefer the Mercedes option.
Visibility: I found the view to be adequate and didn't really notice any issue with the A-pillars.
Fit and finish: The Gravity is a nice looking EV with a good interior but it is not as luxurious as the Mercedes. When we left the Studio to drive home (about an hours drive), the Mercedes feels much more refined and has a better, smoother ride. The Gravity isn't really a luxury car, but it is a very nice car.
So while I realize most on this forum already own a Gravity or have one on order, our test drive today convinced me and my wife that the Gravity is just not right for us. We have another year of warrantee remaining on or EQS SUV so we have time to see what other options may be available. In the end, the test drive confirmed that our Mercedes is an all around better car for our specific needs and wants.
I wish all of you the best!