We find the second row monopost seats to be very comfortable. The range of movement is limited, as noted above.
For albrehti, if you're that disappointed because the second row headrests aren't adjustable, trust me. This isn't the car for you. There is much much more that you'll expect that won't be there. For better or for worse, Tesla it it's own unique thing and while you can cross shop it with cars that cost the same, it's not going after the same goals. It's definitely not a luxury car that happens to be electric. It's an electric car that does things differently. If you like those things, it's the only game in town. If other things are more important, you'll be very disappointed.