Over six feet? Check the length first: the longest of the 19 mattresses compared is 215 cm, and many are 193 cm or shorter. Side sleepers also need enough depth under the hip. Here are the picks.
The Snuuzu Model Y is 205 cm long and 20 cm thick, and owners up to 6'4" (about 193 cm) report that it fits. The EXPED MegaMat Auto is a foam alternative at 197 cm (EXPED also lists 193 cm). The longest of the 19 is the Aerogogo at 215 cm, a pure air bed. Yeslak (204 cm), Luno (203 cm) and the Havnby FlatCore for Model Y L (200 cm, Model Y L only) also reach 200 cm. Many are shorter: Havnby FlatCore, Havnby CloudCore and NovaPads are 193 cm, DreamCase 192 cm, Tesla OEM 191 cm, Tesery and AYAMAYA 188 cm, and TAPTES 180 cm. TESMAT, T-Launch and ForMyTesla publish no length.
205 cm long and 20 cm thick, with comfort foam over a pressurised air layer. Owners up to 6'4" (about 193 cm) report that it fits. It also has the highest price of the 19, and no sleep trial.
197 cm long (EXPED also lists 193 cm) and 132 cm wide, narrowing to 104 cm at the foot, with an R-value of 8.1. A multi-SUV pad rather than a Tesla cut.
193 cm long and 132 cm wide, rated to 300 kg by Havnby, with a fixed taper that offsets the seat slope. At 193 cm it is shorter than the Snuuzu (205 cm) and the EXPED (197 cm), so check it against your height.