First 2021 E-Series video Iíve seen of actual unit at a dealer. I expect they should start to become more common from various manufacturers.
Itís a Nexus Viper 29V and salesman shows inside of cab in first 2 minutes, including starting the new engine so we can hear while idling. Not really an accurate indicator since door is open so much of sound is from outside noise. Still seems quieter but hard to say on a biased sales video.
Video also shows TPMS which includes all six tires on this E-450. Also of interest later in video is a 7.5 cubic foot (all electric) residential fridge by Whirlpool if I recall correctly.