Seems that the 3 hands-on reviews so far were done on the same vehicle, they have the same license plate. This may have been a good measure from tesla to start noticing durability issues before deliveries started.
When on a pinch, a Tesla engineer slept on the floor after having the back seats all the way up.
"It's not quite 6 feet but it is also pretty decent for sleeping" at 33:13.
Any estimate on the measure across the floor?