| Model Year | 2017 | 2018 | |
| Model | Audi A8 / S8 | Mercedes-Benz GLS | |
| Engine | |||
| Transmission | |||
| Drivetrain | |||
| Body | 4dr Sedan, ext. | 4dr SUV | |
| Difference | |||
| Wheelbase | 122.9 in | 121.1 in | 1.8 in |
| Length | 207.4 in | 202.0 in | 5.4 in |
| Width | 76.7 in | 76.1 in | 0.6 in |
| Height | 57.9 in | 72.8 in | -14.9 in |
| Curb Weight | 4464 lb. | 5400 lb. | -936 lb. |
| Fuel Capacity | 21.7 gal. | 26.4 gal. | -4.7 gal. |
| Headroom, Row 1 | 37.2 in | 41.2 in | -4 in |
| Shoulder Room, Row 1 | 59.1 in | 58.5 in | 0.6 in |
| Legroom, Row 1 | 41.4 in | 40.3 in | 1.1 in |
| Headroom, Row 2 | 39.1 in | 40.0 in | -0.9 in |
| Shoulder Room, Row 2 | 57.8 in | 58.3 in | -0.5 in |
| Legroom, Row 2 | 42.9 in | 38.5 in | 4.4 in |
| Headroom, Row 3 | 0.0 in | 38.9 in | -38.9 in |
| Shoulder Room, Row 3 | 0.0 in | 50.5 in | -50.5 in |
| Legroom, Row 3 | 0.0 in | 35.0 in | -35 in |
| Total Legroom | 84.3 in (over 2 rows) | 113.8 in (over 3 rows) | -29.5 in |
| Cargo Volume, Minimum | 14.2 ft3 | 16.0 ft3 | -1.8 ft3 |
| Cargo Volume, Behind R2 | 14.2 | 49.4 ft3 | -35.2 |
| Cargo Volume, Maximum | 14.2 ft3 | 93.8 ft3 | -79.6 ft3 |
None of our members have yet commented on the seat room and comfort of the 2017 Audi A8 / S8.
None of our members have yet commented on the seat room and comfort of the 2018 Mercedes-Benz GLS.